From k5xu at comcast.net Thu Jan 1 10:59:15 2015 From: k5xu at comcast.net (Mike Duke, K5XU) Date: Thu, 01 Jan 2015 10:59:15 -0500 Subject: [AMRadio] Jackson, MS Hamfest, Jan. 23 - 24, 2015 Message-ID: <751eb0e5.1cbb.43b4.b1a2.9960b953e5fd@samobile.net> Come on over, and bring your Stuff! And, be ready to take some different Stuff home! At this posting, tables are still available. See the website for more information. Mike Duke, K5XU CAPITAL CITY HAMFEST JAN. 23&24, 2015 In the Trademart at the State Fairgrounds 1200 Mississippi St, JACKSON MS 39202 Admission: $8/person Children under 12 admitted free ? 2015 ARRL MS Section Convention ? Equipment Check-out table ? WAS & DXCC Checking ? New and Used Ham Radio Gear ? Door Prize drawings ? Military Vehicle Display * Go-Box Competition! See the HAMFEST website for details. VE Testing at 8am Saturday Friday, Jan. 23, 5 PM to 8 PM Saturday, Jan. 24, 8 AM to 4 PM Talk-in on 146.76- (no tone) Backup talk-in on 146.94- GPS Coordinates: 32.30133, - 90.17166 Website: www.hamfest.msham.org - email: hamfest at msham.org From k5xu at comcast.net Thu Jan 1 15:51:06 2015 From: k5xu at comcast.net (Mike Duke, K5XU) Date: Thu, 01 Jan 2015 15:51:06 -0500 Subject: [AMRadio] More about the Jackson, MS Hamfest Message-ID: Following my initial post about our upcoming hamfest on Jan. 23 and 24, 2015, someone emailed me off list with a few questions about the size of the event, etc. Perhaps this information will be of interest to others as you decide whether or not to pay us a visit. Of course, we want you to come on down, up, or over, as the case may be. For the past 10 years, we have drawn over a thousand people per year. The number is usually around 1150, and I think the highest has been 1250. Our flea market has developed into a good source for boat anchors and associated parts. In addition to Mississippi hams, we have a good turnout from areas such as Memphis, New Orleans, Baton Rouge, Shreveport, the Florida panhandle, and much of Alabama. I almost always see some people from Texas, but other than the Houston area, I can't really say what areas of the state are represented. If you decide to come over for both days, let me know, and I will give you some hotel recommendations. -- Mike Duke, K5XU From amradio at mailman.qth.net Thu Jan 1 18:33:39 2015 From: amradio at mailman.qth.net (John King via AMRadio) Date: Thu, 1 Jan 2015 15:33:39 -0800 Subject: [AMRadio] Two 807s modulating 4D32 final tube in Viking1 Message-ID: <1420155219.42311.YahooMailBasic@web160305.mail.bf1.yahoo.com> I am replacing he modulation transformer in a Johnson Viking 1 transmitter and need some experienced and knowledgeable input. to assist me., Does anyone know the approximate impedance of two 807 tubes with at least 600 vdc on the plates that the modulation transformer must match? Secondly, does anyone know the impedance of the 4D32 that the secondary of the modulation transformer must match? I have a Stancor A-3893 60 watt poly-pedance multi-tap modulation transformer.The data sheet can be seen on the AM Window web site. I feel sure that it will match the two 807s to the single 4D32. It was used previously in the modulator circuit that used two 6146 modulator tubes as shown in the ARRL handbooks of the 1960s. I need to know what taps to use. Has any used this poly-pedance modulation transformer in a modulator? Your input will be appreciated. Thanks and 73, John, K5PGW From hbrnut at suddenlink.net Thu Jan 1 19:10:30 2015 From: hbrnut at suddenlink.net (WA5VGO) Date: Thu, 1 Jan 2015 18:10:30 -0600 Subject: [AMRadio] Two 807s modulating 4D32 final tube in Viking1 In-Reply-To: <1420155219.42311.YahooMailBasic@web160305.mail.bf1.yahoo.com> References: <1420155219.42311.YahooMailBasic@web160305.mail.bf1.yahoo.com> Message-ID: The 807's will be about 7000 ohms. The 4D32 will be about 3500 ohms. An exact match isn't necessary. I suggest finding the closes combination that will allow connecting the windings in parallel. The transformer (at least in theory) should be a little hardier if the windings are connected in parallel as opposed to series. 73, Darrell > On Jan 1, 2015, at 5:33 PM, John King via AMRadio wrote: > > I am replacing he modulation transformer in a Johnson Viking 1 transmitter and need some experienced and knowledgeable input. to assist me., Does anyone know the approximate impedance of two 807 tubes with at least 600 vdc on the plates that the modulation transformer must match? > > Secondly, does anyone know the impedance of the 4D32 that the secondary of the modulation transformer must match? > > I have a Stancor A-3893 60 watt poly-pedance multi-tap modulation transformer.The data sheet can be seen on the AM Window web site. > > I feel sure that it will match the two 807s to the single 4D32. It was used previously in the modulator circuit that used two 6146 modulator tubes as shown in the ARRL handbooks of the 1960s. I need to know what taps to use. Has any used this poly-pedance modulation transformer in a modulator? Your input will be appreciated. Thanks and 73, John, K5PGW > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html From knjhanlon at msn.com Thu Jan 1 22:01:27 2015 From: knjhanlon at msn.com (JAMES HANLON) Date: Thu, 1 Jan 2015 20:01:27 -0700 Subject: [AMRadio] Replacing dial cord on an S-38e Hallicrafters RX In-Reply-To: References: Message-ID: Mike, If the dial cord is slipping on the tuning knob shaft and that shaft appears to have been polished smooth, I,d suggest roughening the shaft surface. Use a Dremil tool grinder if you have one or some sand paper. Jim, W8KGI Sent from my iPhone > On Dec 30, 2014, at 9:20 AM, Mike Sprenger wrote: > > Hi > > I'm looking for insight in redoing the dial cord on an S-38E, it's very > close to breaking, and it won't tune from end to end right now, it's > spinning on the tuning knob shaft and is badly frayed as a result. > > Any insight on how to do this relatively easily ? > > Thanks, > Mike > > > -- > Thanks, > Mike Sprenger > (37.9167N 81.1244W is the Summit) > From rbethman at comcast.net Thu Jan 1 23:01:00 2015 From: rbethman at comcast.net (rbethman) Date: Thu, 01 Jan 2015 23:01:00 -0500 Subject: [AMRadio] Replacing dial cord on an S-38e Hallicrafters RX In-Reply-To: References: Message-ID: <54A617FC.6000209@comcast.net> Mike, Basically I agree with Jim. My suggestion is to roughen it up, BUT don't use anything overly coarse. I'd use nothing more coarse than something 100 to 150, and just lightly by hand. It is a matter of finesse. To much is just as bad as would be to polish it. Balance is what you are looking for. Then as has been repeatedly posted on many lists, use musician's rosin on the dial cord. The combination will get it working. Regards, Bob - N0DGN On 1/1/2015 10:01 PM, JAMES HANLON wrote: > Mike, > > If the dial cord is slipping on the tuning knob shaft and that shaft appears to have been polished smooth, I,d suggest roughening the shaft surface. Use a Dremil tool grinder if you have one or some sand paper. > > Jim, W8KGI > Sent from my iPhone > >> On Dec 30, 2014, at 9:20 AM, Mike Sprenger wrote: >> >> Hi >> >> I'm looking for insight in redoing the dial cord on an S-38E, it's very >> close to breaking, and it won't tune from end to end right now, it's >> spinning on the tuning knob shaft and is badly frayed as a result. >> >> Any insight on how to do this relatively easily ? >> >> Thanks, >> Mike From mikesprenger at gmail.com Thu Jan 1 23:24:20 2015 From: mikesprenger at gmail.com (Mike Sprenger) Date: Thu, 1 Jan 2015 23:24:20 -0500 Subject: [AMRadio] Replacing dial cord on an S-38e Hallicrafters RX In-Reply-To: <54A617FC.6000209@comcast.net> References: <54A617FC.6000209@comcast.net> Message-ID: Super, Thanks Jim / Bob, et. al....I'm sure the knob shaft is now smooth. I think I will replace the string, as there's more strands frayed away now than wrapped around the tuning knob.... Suggestions for the type of string to use ? Thanks, Mike On Thursday, January 1, 2015, rbethman wrote: > Mike, > > Basically I agree with Jim. My suggestion is to roughen it up, BUT don't > use anything overly coarse. > > I'd use nothing more coarse than something 100 to 150, and just lightly by > hand. > > It is a matter of finesse. To much is just as bad as would be to polish it. > > Balance is what you are looking for. > > Then as has been repeatedly posted on many lists, use musician's rosin on > the dial cord. > > The combination will get it working. > > Regards, Bob - N0DGN > > > On 1/1/2015 10:01 PM, JAMES HANLON wrote: > >> Mike, >> >> If the dial cord is slipping on the tuning knob shaft and that shaft >> appears to have been polished smooth, I,d suggest roughening the shaft >> surface. Use a Dremil tool grinder if you have one or some sand paper. >> >> Jim, W8KGI >> Sent from my iPhone >> >> On Dec 30, 2014, at 9:20 AM, Mike Sprenger >>> wrote: >>> >>> Hi >>> >>> I'm looking for insight in redoing the dial cord on an S-38E, it's very >>> close to breaking, and it won't tune from end to end right now, it's >>> spinning on the tuning knob shaft and is badly frayed as a result. >>> >>> Any insight on how to do this relatively easily ? >>> >>> Thanks, >>> Mike >>> >> > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > -- Thanks, Mike Sprenger (37.9167N 81.1244W is the Summit) From rbethman at comcast.net Fri Jan 2 00:03:26 2015 From: rbethman at comcast.net (rbethman) Date: Fri, 02 Jan 2015 00:03:26 -0500 Subject: [AMRadio] Replacing dial cord on an S-38e Hallicrafters RX In-Reply-To: References: <54A617FC.6000209@comcast.net> Message-ID: <54A6269E.5060604@comcast.net> You can obtain dial cord @ as one source. Others are known to use the braided fishing line. Readily available at WalMart or any fishing sports supplier. It will very likely be less expensive. Remember the musician's rosin to apply to the dial cord. Just a dab will do. Regards, Bob - N0DGN On 1/1/2015 11:24 PM, Mike Sprenger wrote: > Super, > > Thanks Jim / Bob, et. al....I'm sure the knob shaft is now smooth. > > I think I will replace the string, as there's more strands frayed > away now than wrapped around the tuning knob.... > > Suggestions for the type of string to use ? > > Thanks, > Mike From bjtatum1 at att.net Fri Jan 2 11:38:17 2015 From: bjtatum1 at att.net (Byron Tatum) Date: Fri, 2 Jan 2015 08:38:17 -0800 Subject: [AMRadio] Murata Ceramic Filter Message-ID: <1420216697.75158.YahooMailNeo@web181506.mail.ne1.yahoo.com> Hello- I am studying adding a Murata 455 KHz ceramic IF filter in a low power tube-type AM transceiver. Which is a good one? I am wanting around 6 KHz bandwidth; not interested in real high fidelity necessarily but mostly good AM selectivity. Thanks, Byron WA5THJ From ranchorobbo at gmail.com Fri Jan 2 13:14:13 2015 From: ranchorobbo at gmail.com (Rob Atkinson) Date: Fri, 2 Jan 2015 12:14:13 -0600 Subject: [AMRadio] Murata Ceramic Filter In-Reply-To: <1420216697.75158.YahooMailNeo@web181506.mail.ne1.yahoo.com> References: <1420216697.75158.YahooMailNeo@web181506.mail.ne1.yahoo.com> Message-ID: It's better to just jump the filter slot with a wire and do your bandwidth limiting in the audio to the rig via a low pass filter. 73 Rob K5UJ On Fri, Jan 2, 2015 at 10:38 AM, Byron Tatum wrote: > Hello- > I am studying adding a Murata 455 KHz ceramic IF filter in a low power tube-type AM transceiver. Which is a good one? I am wanting around 6 KHz bandwidth; not interested in real high fidelity necessarily but mostly good AM selectivity. > Thanks, Byron WA5THJ > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html From Tonne at Comcast.net Fri Jan 2 13:51:42 2015 From: Tonne at Comcast.net (Jim Tonne) Date: Fri, 02 Jan 2015 13:51:42 -0500 Subject: [AMRadio] Murata Ceramic Filter In-Reply-To: References: <1420216697.75158.YahooMailNeo@web181506.mail.ne1.yahoo.com> Message-ID: <54A6E8BE.9080809@Comcast.net> Rob: Are you suggesting no filtering at all in the I.F. ?? - JimT W4ENE On 1/2/2015 1:14 PM, Rob Atkinson wrote: > It's better to just jump the filter slot with a wire and do your > bandwidth limiting in the audio to the rig via a low pass filter. > > 73 > Rob > K5UJ > From ranickel at comcast.net Fri Jan 2 14:05:54 2015 From: ranickel at comcast.net (Robert Nickels) Date: Fri, 02 Jan 2015 13:05:54 -0600 Subject: [AMRadio] Murata Ceramic Filter In-Reply-To: References: <1420216697.75158.YahooMailNeo@web181506.mail.ne1.yahoo.com> Message-ID: <54A6EC12.7070800@comcast.net> Byron, These filters are rapidly becoming obsolete, but have a look on the cheap filters toward the bottom of this page from Surplus Sales of Nebraska: http://www.surplussales.com/Filters/Filters-1.html 73, Bob W9RAN From ranchorobbo at gmail.com Fri Jan 2 14:15:33 2015 From: ranchorobbo at gmail.com (Rob Atkinson) Date: Fri, 2 Jan 2015 13:15:33 -0600 Subject: [AMRadio] Murata Ceramic Filter In-Reply-To: <54A6E8BE.9080809@Comcast.net> References: <1420216697.75158.YahooMailNeo@web181506.mail.ne1.yahoo.com> <54A6E8BE.9080809@Comcast.net> Message-ID: Yes I am. You have to have a separate receiver like with most AM stations. 73 Rob K5UJ On Fri, Jan 2, 2015 at 12:51 PM, Jim Tonne wrote: > > > > Rob: > > Are you suggesting no filtering at all in the I.F. ?? > > - JimT W4ENE > > > > > On 1/2/2015 1:14 PM, Rob Atkinson wrote: >> >> It's better to just jump the filter slot with a wire and do your >> bandwidth limiting in the audio to the rig via a low pass filter. >> >> 73 >> Rob >> K5UJ >> > > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html From knjhanlon at msn.com Fri Jan 2 15:49:31 2015 From: knjhanlon at msn.com (JAMES HANLON) Date: Fri, 2 Jan 2015 13:49:31 -0700 Subject: [AMRadio] [AMRadio} Murata Ceramic Filter Message-ID: Byron, You might want to consider a Collins mechanical filter instead. Go to ebay, Ham and Amatuer Radio and search for "Collins Filter." You will find a listing, "Collins Mechanical Filter 455 KC CF, 7.6 KHz BW Symmetrical (AM) NOS." The title pretty much describes it. It sells for $80 plus $7.50 shipping. They are described as New Old Stock from Watkins Johnson, as used in receivers like the WJ-7800. I bought a nominal 200 cycle bandwidth filter from this person last year, and it is working fine in my HRO-50 today. They also have ebay listings for filters with 100 Hz, 200 Hz, 1.2 KHz, 4 KHz and 16 KHz bandwidths. 73, Jim Hanlon, W8KGI From bjtatum1 at att.net Sat Jan 3 13:33:25 2015 From: bjtatum1 at att.net (Byron Tatum) Date: Sat, 3 Jan 2015 10:33:25 -0800 Subject: [AMRadio] Incorporating AM Ceramic Filter In Tube Radio Message-ID: <1420310005.27500.YahooMailNeo@web181504.mail.ne1.yahoo.com> Hello- Can anyone suggest the best way to incorporate a 455 KHz ceramic filter (impedance is 1500 ohms) into the IF amplifier chain of a tube receiver? I wish to add the AM bandwidth filter (NTK LF-D6) at the start of my 2 stage 6BA6 IF amplifier chain. There is a pair of conventional type IF transformers (each transformer has a pair of tuned circuits), the transformer pair lightly coupled with a 2.2 pF cap. The first 455 KHz IF transformer of this pair has its primary feeding B+ to the second mixer plate circuit (6.0 Mhz to 455 KHz.) The secondary of this first 455 KHz IF has one end grounded and the other end connected to the 2.2 pF coupling cap. The other end of the coupling cap is attached to the primary of the second 455 Khz IF transformer; the other end of its primary winding being grounded. The secondary of this second 455 KHz IF transformer is directly connected to the grid of the 6BA6 first IF amplifier, with AVC feed (bypassed by capacitor) connected to other end of secondary. Can someone suggest the best manner in order to properly match the low impedance input/output of ceramic filter with the minimum of loss? Thanks, Byron WA5THJ From macklinbob at gmail.com Sat Jan 3 13:56:16 2015 From: macklinbob at gmail.com (K5MYJ) Date: Sat, 3 Jan 2015 10:56:16 -0800 Subject: [AMRadio] Incorporating AM Ceramic Filter In Tube Radio References: <1420310005.27500.YahooMailNeo@web181504.mail.ne1.yahoo.com> Message-ID: <675F56A0B7274894A4816EB0A41BC592@IVORYTOWER> Why do you need an AM filter? What is the radio you are trying to modify? Bob Macklin K5MYJ Seattle, Wa. "Real Radios Glow In The Dark" ----- Original Message ----- From: "Byron Tatum" To: Sent: Saturday, January 03, 2015 10:33 AM Subject: [AMRadio] Incorporating AM Ceramic Filter In Tube Radio > Hello- > Can anyone suggest the best way to incorporate a 455 KHz ceramic filter > (impedance is 1500 ohms) into the IF amplifier chain of a tube receiver? > I wish to add the AM bandwidth filter (NTK LF-D6) at the start of my 2 > stage 6BA6 IF amplifier chain. There is a pair of conventional type IF > transformers (each transformer has a pair of tuned circuits), the > transformer pair lightly coupled with a 2.2 pF cap. > The first 455 KHz IF transformer of this pair has its primary feeding B+ > to the second mixer plate circuit (6.0 Mhz to 455 KHz.) The secondary of > this first 455 KHz IF has one end grounded and the other end connected to > the 2.2 pF coupling cap. The other end of the coupling cap is attached to > the primary of the second 455 Khz IF transformer; the other end of its > primary winding being grounded. The secondary of this second 455 KHz IF > transformer is directly connected to the grid of the 6BA6 first IF > amplifier, with AVC feed (bypassed by capacitor) connected to other end of > secondary. > Can someone suggest the best manner in order to properly match the low > impedance input/output of ceramic filter with the minimum of loss? > Thanks, Byron WA5THJ > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html From w5jo at brightok.net Tue Jan 6 08:11:46 2015 From: w5jo at brightok.net (Jim Wilhite) Date: Tue, 6 Jan 2015 07:11:46 -0600 Subject: [AMRadio] Posted on another reflector Message-ID: <8CE08FC4220746D18F109FFB126F8028@JimPC> HX-50 transmitter and HQ-170 Receiver. Both are 100% mint $375.00 each or $650.00 pair. W5RER 405-240-8554 SW OKC __._,_.___ From k2owr at comcast.net Tue Jan 6 12:23:37 2015 From: k2owr at comcast.net (k4owr) Date: Tue, 06 Jan 2015 12:23:37 -0500 Subject: [AMRadio] AM station FS Message-ID: <54AC1A19.3020409@comcast.net> :::: Completely restored and working beautifully: National NC-300 $300 Johnson Valiant II $550 D-104 Mic. $50 Would like to sell all together $850 Will ship but they're heavy! $$$ Meet somewhere? can be seen at www.QRZ.com search K4OWR From w6zkh at att.net Tue Jan 6 12:24:40 2015 From: w6zkh at att.net (John Neeley) Date: Tue, 6 Jan 2015 09:24:40 -0800 Subject: [AMRadio] Kenwood MC-50 mike with AM gear Message-ID: <1420565080.5469.YahooMailNeo@web184804.mail.gq1.yahoo.com> I have a Kenwood MC-50 mike and am wondering if I can use it with my older, tube type AM gear, like the HT-32a, Valiant or DX-100? Otherwise if not, will need to get a old D-104, etc. Any info would be greatly appreciated. John W6ZKH From cw_de_n5op at sbcglobal.net Tue Jan 6 13:38:25 2015 From: cw_de_n5op at sbcglobal.net (Kim Elmore) Date: Tue, 6 Jan 2015 11:38:25 -0700 Subject: [AMRadio] Kenwood MC-50 mike with AM gear In-Reply-To: <1420565080.5469.YahooMailNeo@web184804.mail.gq1.yahoo.com> References: <1420565080.5469.YahooMailNeo@web184804.mail.gq1.yahoo.com> Message-ID: Should be fine. I use an MC-60 with Globe Champ 350 and have had some nice compliments on the audio. Kim N5OP "People that make music together cannot be enemies, at least as long as the music lasts." -- Paul Hindemith > On Jan 6, 2015, at 10:24, John Neeley wrote: > > I have a Kenwood MC-50 mike and am wondering if I can use it with my older, tube type AM gear, like the HT-32a, Valiant or DX-100? Otherwise if not, will need to get a old D-104, etc. Any info would be greatly appreciated. > > John W6ZKH > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html From manualman at juno.com Tue Jan 6 15:17:23 2015 From: manualman at juno.com (manualman at juno.com) Date: Tue, 6 Jan 2015 15:17:23 -0500 Subject: [AMRadio] Kenwood MC-50 mike with AM gear Message-ID: I had a MC-50 for many years. It came with my TS-830. The mike can be connected as either high or low impedance. To switch impedance, rotate either connector (not both) 180 degrees on the short piece of cable between the mike and the stand. However, the mike was designed for SSB use. Hooking it up to several vintage transmitters, I never found the AM quality to be exceptional. Actually, on several of my vintage transmitters, my $1.95 Lafayette lapel mike sounded better. Bottom line, if that's all you have, it will work. Pete, wa2cwa On Tue, 6 Jan 2015 09:24:40 -0800 John Neeley writes: > I have a Kenwood MC-50 mike and am wondering if I can use it with my > older, tube type AM gear, like the HT-32a, Valiant or DX-100? > Otherwise if not, will need to get a old D-104, etc. Any info would > be greatly appreciated. > > John W6ZKH From ars.w5omr at gmail.com Wed Jan 7 08:35:46 2015 From: ars.w5omr at gmail.com (Geoff) Date: Wed, 07 Jan 2015 07:35:46 -0600 Subject: [AMRadio] Kenwood MC-50 mike with AM gear In-Reply-To: References: Message-ID: <54AD3632.6090404@gmail.com> On 01/06/2015 02:17 PM, manualman at juno.com wrote: > I had a MC-50 for many years. It came with my TS-830. The mike can be > connected as either high or low impedance. To switch impedance, rotate > either connector (not both) 180 degrees on the short piece of cable > between the mike and the stand. However, the mike was designed for SSB > use. Hooking it up to several vintage transmitters, I never found the AM > quality to be exceptional. Actually, on several of my vintage > transmitters, my $1.95 Lafayette lapel mike sounded better. Bottom line, > if that's all you have, it will work. After a fashion, I suppose... The issue is, that the Low and High impedance choices on the MC-50 are 500 and 5000 ohms. Typical 6AU6/12AX7 input impedance is upwards of 500,000 to 1 Meg-ohm. Depending on how well stocked your junk box is, you may already have the solution. A 10:1 transformer (120/12v) can take the 5000 ohm impedance and bump it up closer to what the older tube gear is looking for. Gotta love Electronics... "The Exacting Science of approximation." -73 = Best Regards, -Geoff/W5OMR From manualman at juno.com Wed Jan 7 13:32:46 2015 From: manualman at juno.com (manualman at juno.com) Date: Wed, 7 Jan 2015 13:32:46 -0500 Subject: [AMRadio] Kenwood MC-50 mike with AM gear Message-ID: The Hi-Z on the MC-50 is 50K not 5K. Pete, wa2cwa On Wed, 07 Jan 2015 07:35:46 -0600 Geoff writes: > > After a fashion, I suppose... > > The issue is, that the Low and High impedance choices on the MC-50 > are > 500 and 5000 ohms. > Typical 6AU6/12AX7 input impedance is upwards of 500,000 to 1 > Meg-ohm. > > Depending on how well stocked your junk box is, you may already have > the > solution. > > A 10:1 transformer (120/12v) can take the 5000 ohm impedance and > bump it > up closer to what the older tube gear is looking for. > > Gotta love Electronics... "The Exacting Science of approximation." > > -73 = Best Regards, > -Geoff/W5OMR From cw_de_n5op at sbcglobal.net Wed Jan 7 15:32:57 2015 From: cw_de_n5op at sbcglobal.net (Kim Elmore) Date: Wed, 7 Jan 2015 13:32:57 -0700 Subject: [AMRadio] Kenwood MC-50 mike with AM gear In-Reply-To: References: Message-ID: <20659A82-7B4C-441F-A095-FBD0B956260A@sbcglobal.net> FWIW, the MC-60 has a switch that allows me to select either 500 or 50k ohms impedance. I've tried both: selecting 500 requires that I increase the input gain on the Globe Champ a bit but that's about the only difference. Kim N5OP "People that make music together cannot be enemies, at least as long as the music lasts." -- Paul Hindemith > On Jan 7, 2015, at 11:32, wrote: > > The Hi-Z on the MC-50 is 50K not 5K. > Pete, wa2cwa > > On Wed, 07 Jan 2015 07:35:46 -0600 Geoff writes: >> >> After a fashion, I suppose... >> >> The issue is, that the Low and High impedance choices on the MC-50 >> are >> 500 and 5000 ohms. >> Typical 6AU6/12AX7 input impedance is upwards of 500,000 to 1 >> Meg-ohm. >> >> Depending on how well stocked your junk box is, you may already have >> the >> solution. >> >> A 10:1 transformer (120/12v) can take the 5000 ohm impedance and >> bump it >> up closer to what the older tube gear is looking for. >> >> Gotta love Electronics... "The Exacting Science of approximation." >> >> -73 = Best Regards, >> -Geoff/W5OMR > > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html From manualman at juno.com Wed Jan 7 15:45:53 2015 From: manualman at juno.com (manualman at juno.com) Date: Wed, 7 Jan 2015 15:45:53 -0500 Subject: [AMRadio] Kenwood MC-50 mike with AM gear Message-ID: The MC-50 and MC-60, I believe, use similar, if not identical, microphone elements. However, the MC-60 comes with a mike preamp; the MC-50 does not. Pete, wa2wa On Wed, 7 Jan 2015 13:32:57 -0700 Kim Elmore writes: FWIW, the MC-60 has a switch that allows me to select either 500 or 50k ohms impedance. I've tried both: selecting 500 requires that I increase the input gain on the Globe Champ a bit but that's about the only difference. Kim N5OP From cw_de_n5op at sbcglobal.net Wed Jan 7 18:04:50 2015 From: cw_de_n5op at sbcglobal.net (Kim Elmore) Date: Wed, 7 Jan 2015 16:04:50 -0700 Subject: [AMRadio] Kenwood MC-50 mike with AM gear In-Reply-To: References: Message-ID: <4F3898F4-1F3E-4D5C-8364-60DD8B08FC47@sbcglobal.net> Correct. I don't use the preamp at all. It also adds it's own response curve, which is decidedly NOT flat. Kim N5OP "People that make music together cannot be enemies, at least as long as the music lasts." -- Paul Hindemith > On Jan 7, 2015, at 13:45, wrote: > > The MC-50 and MC-60, I believe, use similar, if not identical, microphone > elements. However, the MC-60 comes with a mike preamp; the MC-50 does > not. > > Pete, wa2wa > > > On Wed, 7 Jan 2015 13:32:57 -0700 Kim Elmore > writes: > FWIW, the MC-60 has a switch that allows me to select either 500 or 50k > ohms impedance. I've tried both: selecting 500 requires that I increase > the input gain on the Globe Champ a bit but that's about the only > difference. > > > Kim N5OP > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html From k5xu at comcast.net Fri Jan 9 10:26:52 2015 From: k5xu at comcast.net (Mike Duke, K5XU) Date: Fri, 09 Jan 2015 10:26:52 -0500 Subject: [AMRadio] Tube Lineup for S19R Receiver Message-ID: <299c537b.df58.4c59.ac8e.89acc5a118b3@samobile.net> I am trying to help a non-ham friend find parts to resurrect his dad's old S19R. Will someone please email me the tube lineup off list? There is at least one tube that we cannot identify because the numbers are completely gone from it. Also, where would we be able to locate a schematic? -- Mike Duke, K5XU From w4wsz at embarqmail.com Fri Jan 9 15:35:27 2015 From: w4wsz at embarqmail.com (Bob) Date: Fri, 9 Jan 2015 15:35:27 -0500 Subject: [AMRadio] Tube Lineup for S19R Receiver In-Reply-To: <299c537b.df58.4c59.ac8e.89acc5a118b3@samobile.net> References: <299c537b.df58.4c59.ac8e.89acc5a118b3@samobile.net> Message-ID: <003601d02c4b$ce42fb90$6ac8f2b0$@embarqmail.com> Mike, The tube line up is: 6K8, 6SK7, 6SQ7, 41, 80, and 76. The 80 is replaced by a 5Y3 and the 76 with a 6C5 The 41 was replaced with the 6F6. Complete manual and schematic is on the BAMA web site 73, Bob, W4WSZ -----Original Message----- From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of Mike Duke, K5XU Sent: Friday, January 09, 2015 10:27 AM To: amradio at mailman.qth.net Subject: [AMRadio] Tube Lineup for S19R Receiver I am trying to help a non-ham friend find parts to resurrect his dad's old S19R. Will someone please email me the tube lineup off list? There is at least one tube that we cannot identify because the numbers are completely gone from it. Also, where would we be able to locate a schematic? -- Mike Duke, K5XU ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Archives: http://mailman.qth.net/pipermail/amradio/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: AMRadio at mailman.qth.net To unsubscribe, send an email to amradio-request at mailman.qth.net with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com From jc at pctechref.com Mon Jan 12 16:33:29 2015 From: jc at pctechref.com (John Coleman) Date: Mon, 12 Jan 2015 15:33:29 -0600 Subject: [AMRadio] Kenwood MC-50 mike with AM gear In-Reply-To: <1420565080.5469.YahooMailNeo@web184804.mail.gq1.yahoo.com> References: <1420565080.5469.YahooMailNeo@web184804.mail.gq1.yahoo.com> Message-ID: <002701d02eaf$68b596f0$3a20c4d0$@com> Hi John, A lot of the old rigs did not even have a coupling capacitor to the grid of the preamp stage. This is of no consequence when using a crystal/ceramic microphone, but other mics may drain your grid bias on the preamp tube and cause a lot of distortion. If the coupling cap is not there put one in. .01 to .05 is good. Also a lot of the modern microphones have way to much bass response for the old rigs modulator and modulation XFMR. A coupling capacitor in series with the microphone cable and a resistor across the cable on the rig side of the coupling capacitor will reduce the low frequency response. Start with a .05 uf and 100K resistor. Decreasing the value of either will reduce low frequency output and vice versa. Don't worry about matching impedance. The 1 or 2 meg resistor at the preamp grid is there for what is known as contact bias. And it works well with the crystal/ceramic microphone as they actually have their best response with no load or very high resistance. Good Luck, John, WA5BXO -----Original Message----- From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of John Neeley Sent: Tuesday, January 06, 2015 11:25 AM To: amradio at mailman.qth.net Subject: [AMRadio] Kenwood MC-50 mike with AM gear I have a Kenwood MC-50 mike and am wondering if I can use it with my older, tube type AM gear, like the HT-32a, Valiant or DX-100? Otherwise if not, will need to get a old D-104, etc. Any info would be greatly appreciated. John W6ZKH ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Archives: http://mailman.qth.net/pipermail/amradio/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: AMRadio at mailman.qth.net To unsubscribe, send an email to amradio-request at mailman.qth.net with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html From w5jo at brightok.net Mon Jan 12 16:57:41 2015 From: w5jo at brightok.net (Jim Wilhite) Date: Mon, 12 Jan 2015 15:57:41 -0600 Subject: [AMRadio] Hi current ceramic switches Message-ID: <827ABE5A4A054F2DB9D0CD33DC3F7A81@JimPC> Once upon a time I had the name and web site link of the company who makes high current ceramic rotary switches for RF. The switches were originally Centralab, but they were bought by someone and are still being manufactured. I consolidated my favorite list and lost the information. Ameritron uses them in their high power amplifiers, which is the 80 series. A search on the web turns up so many answers I am cross eyed trying to find the manufacturer. So does anyone have the link to the site in question? Jim W5JO From james.liles at comcast.net Mon Jan 12 17:30:25 2015 From: james.liles at comcast.net (james.liles at comcast.net) Date: Mon, 12 Jan 2015 16:30:25 -0600 Subject: [AMRadio] Hi current ceramic switches In-Reply-To: <827ABE5A4A054F2DB9D0CD33DC3F7A81@JimPC> References: <827ABE5A4A054F2DB9D0CD33DC3F7A81@JimPC> Message-ID: Multi-tech. They bought Centralab and Oak but they no longer make the original switches. They do however make the series 80 as well as many others. What radio is it for? Kindest regards Jim K9AXN -----Original Message----- From: Jim Wilhite Sent: Monday, January 12, 2015 3:57 PM To: AM Radio List Subject: [AMRadio] Hi current ceramic switches Once upon a time I had the name and web site link of the company who makes high current ceramic rotary switches for RF. The switches were originally Centralab, but they were bought by someone and are still being manufactured. I consolidated my favorite list and lost the information. Ameritron uses them in their high power amplifiers, which is the 80 series. A search on the web turns up so many answers I am cross eyed trying to find the manufacturer. So does anyone have the link to the site in question? Jim W5JO ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Archives: http://mailman.qth.net/pipermail/amradio/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: AMRadio at mailman.qth.net To unsubscribe, send an email to amradio-request at mailman.qth.net with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html From macklinbob at gmail.com Mon Jan 12 17:34:14 2015 From: macklinbob at gmail.com (K5MYJ) Date: Mon, 12 Jan 2015 14:34:14 -0800 Subject: [AMRadio] Hi current ceramic switches References: <827ABE5A4A054F2DB9D0CD33DC3F7A81@JimPC> Message-ID: <0EB729F705864175AB92B0A4667CF42A@IVORYTOWER> Try ElectroSwitch. They are the old Centralab switches. Mouser and DigiKey carry them. Bob Macklin K5MYJ Seattle, Wa. "Real Radios Glow In The Dark" ----- Original Message ----- From: "Jim Wilhite" To: "AM Radio List" Sent: Monday, January 12, 2015 1:57 PM Subject: [AMRadio] Hi current ceramic switches > Once upon a time I had the name and web site link of the company who makes > high current ceramic rotary switches for RF. The switches were originally > Centralab, but they were bought by someone and are still being > manufactured. I consolidated my favorite list and lost the information. > Ameritron uses them in their high power amplifiers, which is the 80 > series. > > A search on the web turns up so many answers I am cross eyed trying to > find the manufacturer. So does anyone have the link to the site in > question? > > Jim > W5JO > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html From frsahu0003 at embarqmail.com Mon Jan 12 19:09:54 2015 From: frsahu0003 at embarqmail.com (FRANK HUGHES hughes) Date: Mon, 12 Jan 2015 19:09:54 -0500 (EST) Subject: [AMRadio] Using an old Collins amp for AM In-Reply-To: <439837849.24255178.1421107781231.JavaMail.root@embarqmail.com> Message-ID: <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> Hi, I would like to be able to participate in some of the AM nets. My 32V-2 only makes 70 watts of carrier. (low voltage selected) I have a good condition Collins 30S-1 that I normally use for SSB. If the power is kept down to about 150 watts of carrier, could I drive the amp w/ the 32V-2? My first homebrew amp is under construction, but until it is ready, I am hoping to find a temporary solution. 73 Frank KJ4OLL From hbrnut at suddenlink.net Mon Jan 12 19:19:15 2015 From: hbrnut at suddenlink.net (WA5VGO) Date: Mon, 12 Jan 2015 18:19:15 -0600 Subject: [AMRadio] Using an old Collins amp for AM In-Reply-To: <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> References: <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> Message-ID: Increasing your power from 70 watts to 150 watts will make almost no noticeable difference on the receiving end. Generally a three or four fold increase is worthwhile. Anything less is pretty useless unless conditions are very marginal. If you have never used a linear amplifier for AM you might want to investigate using one. It's brutal on the amplifier and if the amplifier isn't tuned correctly it's brutal on adjacent QSO's. 73, Darrell > On Jan 12, 2015, at 6:09 PM, FRANK HUGHES hughes wrote: > > Hi, > I would like to be able to participate in some of the AM nets. > My 32V-2 only makes 70 watts of carrier. (low voltage selected) > I have a good condition Collins 30S-1 that I normally use for SSB. > If the power is kept down to about 150 watts of carrier, could I drive the amp w/ the 32V-2? > > > My first homebrew amp is under construction, but until it is ready, I am hoping to find a temporary > solution. > 73 > Frank > KJ4OLL > From wa9vrh at wildblue.net Mon Jan 12 19:20:33 2015 From: wa9vrh at wildblue.net (wa9vrh) Date: Mon, 12 Jan 2015 18:20:33 -0600 Subject: [AMRadio] Using an old Collins amp for AM In-Reply-To: <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> References: <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> Message-ID: <54B464D1.4020206@wildblue.net> Hi Frank, Have you tried using the 32V-2 on AM. For the Collins Collectors 1st Wednesday AM net I have been using an Elmac AF-68 which runs less power than your 32V-2. Might give the 32V-2 a try. 73 Larry WA9VRH On 1/12/2015 6:09 PM, FRANK HUGHES hughes wrote: > Hi, > I would like to be able to participate in some of the AM nets. > My 32V-2 only makes 70 watts of carrier. (low voltage selected) > I have a good condition Collins 30S-1 that I normally use for SSB. > If the power is kept down to about 150 watts of carrier, could I drive the amp w/ the 32V-2? > > > My first homebrew amp is under construction, but until it is ready, I am hoping to find a temporary > solution. > 73 > Frank > KJ4OLL > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > From ranchorobbo at gmail.com Mon Jan 12 19:42:18 2015 From: ranchorobbo at gmail.com (Rob Atkinson) Date: Mon, 12 Jan 2015 18:42:18 -0600 Subject: [AMRadio] Using an old Collins amp for AM In-Reply-To: <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> References: <439837849.24255178.1421107781231.JavaMail.root@embarqmail.com> <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> Message-ID: Just run the collins rig into the antenna. It should put out at least 100 w. You might need to change the 4D32. 73 Rob K5UJ On Mon, Jan 12, 2015 at 6:09 PM, FRANK HUGHES hughes wrote: > Hi, > I would like to be able to participate in some of the AM nets. > My 32V-2 only makes 70 watts of carrier. (low voltage selected) > I have a good condition Collins 30S-1 that I normally use for SSB. > If the power is kept down to about 150 watts of carrier, could I drive the amp w/ the 32V-2? > From wf2u at ws19ops.com Mon Jan 12 20:10:30 2015 From: wf2u at ws19ops.com (Meir WF2U) Date: Mon, 12 Jan 2015 20:10:30 -0500 Subject: [AMRadio] Using an old Collins amp for AM In-Reply-To: <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> References: <439837849.24255178.1421107781231.JavaMail.root@embarqmail.com> <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> Message-ID: <6F7CCCE6C3CC440EBF95011F96C7DAE9@MBDCONSULTING.LOCAL> Raising the carrier from 70W to 150W means about gaining 1/2 of an S-point on the receiving end. 1 S-point is 6 dB increase in power, which is quadrupling it, as if you increased from 70 to 280 W carrier. Doubling the power is 3 dB, which is a half S-point. It's not worth the effort. 73, Meir WF2U Landrum, SC -----Original Message----- From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of FRANK HUGHES hughes Sent: Monday, January 12, 2015 7:10 PM To: amradio at mailman.qth.net Subject: [AMRadio] Using an old Collins amp for AM Hi, I would like to be able to participate in some of the AM nets. My 32V-2 only makes 70 watts of carrier. (low voltage selected) I have a good condition Collins 30S-1 that I normally use for SSB. If the power is kept down to about 150 watts of carrier, could I drive the amp w/ the 32V-2? My first homebrew amp is under construction, but until it is ready, I am hoping to find a temporary solution. 73 Frank KJ4OLL ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Archives: http://mailman.qth.net/pipermail/amradio/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: AMRadio at mailman.qth.net To unsubscribe, send an email to amradio-request at mailman.qth.net with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html From paul at paulbaldock.com Mon Jan 12 20:42:21 2015 From: paul at paulbaldock.com (Paul Baldock) Date: Mon, 12 Jan 2015 17:42:21 -0800 Subject: [AMRadio] Using an old Collins amp for AM In-Reply-To: <6F7CCCE6C3CC440EBF95011F96C7DAE9@MBDCONSULTING.LOCAL> References: <439837849.24255178.1421107781231.JavaMail.root@embarqmail.com> <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> <6F7CCCE6C3CC440EBF95011F96C7DAE9@MBDCONSULTING.LOCAL> Message-ID: It's definitely worth the effort, 3dB is very significant for a marginal signal. However with your 30S1 you should be able to easily get 250W carrier and 1000W PEP which is 5.5dB more than your 70W. If you have modified your 30S1 for higher screen voltage, then you can get 1500W PEP and 375W carrier which is legal limit in the USA. You will only need 30W or so of carrier drive for, so for best modulation characteristics you should put an attenuator between the the driver rig and the 30S1 and then tune the driver for 70W (or 100W if that really is the spec). Don't forge to tune the linear for maximum PEP and NOT for maximum carrier. The carrier level should be 25% of the PEP. - Paul KW7Y At 05:10 PM 1/12/2015, you wrote: >Raising the carrier from 70W to 150W means about gaining 1/2 of an S-point >on the receiving end. 1 S-point is 6 dB increase in power, which is >quadrupling it, as if you increased from 70 to 280 W carrier. Doubling the >power is 3 dB, which is a half S-point. >It's not worth the effort. > >73, Meir WF2U >Landrum, SC > >-----Original Message----- >From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of FRANK >HUGHES hughes >Sent: Monday, January 12, 2015 7:10 PM >To: amradio at mailman.qth.net >Subject: [AMRadio] Using an old Collins amp for AM > >Hi, >I would like to be able to participate in some of the AM nets. >My 32V-2 only makes 70 watts of carrier. (low voltage selected) >I have a good condition Collins 30S-1 that I normally use for SSB. >If the power is kept down to about 150 watts of carrier, could I drive the >amp w/ the 32V-2? > > >My first homebrew amp is under construction, but until it is ready, I am >hoping to find a temporary >solution. >73 >Frank >KJ4OLL >______________________________________________________________ >Our Main Website: http://www.amfone.net >AMRadio mailing list >Archives: http://mailman.qth.net/pipermail/amradio/ >List Rules (must read!): http://w5ami.net/amradiofaq.html >List Home: http://mailman.qth.net/mailman/listinfo/amradio >Post: AMRadio at mailman.qth.net >To unsubscribe, send an email to amradio-request at mailman.qth.net with >the word unsubscribe in the message body. > >This list hosted by: http://www.qsl.net >Please help support this email list: http://www.qsl.net/donate.html > >______________________________________________________________ >Our Main Website: http://www.amfone.net >AMRadio mailing list >Archives: http://mailman.qth.net/pipermail/amradio/ >List Rules (must read!): http://w5ami.net/amradiofaq.html >List Home: http://mailman.qth.net/mailman/listinfo/amradio >Post: AMRadio at mailman.qth.net >To unsubscribe, send an email to amradio-request at mailman.qth.net with >the word unsubscribe in the message body. > >This list hosted by: http://www.qsl.net >Please help support this email list: http://www.qsl.net/donate.html --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com From garyschafer at largeriver.net Mon Jan 12 22:41:27 2015 From: garyschafer at largeriver.net (Gary Schafer) Date: Mon, 12 Jan 2015 21:41:27 -0600 Subject: [AMRadio] Kenwood MC-50 mike with AM gear In-Reply-To: <002701d02eaf$68b596f0$3a20c4d0$@com> References: <1420565080.5469.YahooMailNeo@web184804.mail.gq1.yahoo.com> <002701d02eaf$68b596f0$3a20c4d0$@com> Message-ID: Hello John, A little story about mikes. A long time ago I had a heath SB100 transceiver that I had a dynamic mike hooked to. The mike had a transformer in it. Everything worked fine. I decided to hook up a D104 crystal mike to the rig. It had low and distorted audio. I went to the radio store and got a new element for the D104, same thing. Took the element back for another one and it was the same. I finally swapped out the first audio tube and everything worked great. Turns out that the first audio tube (6U8 I think) had grid leakage. With the transformer mike it held the grid at ground (the grid was direct connected to the mike jack thru a resistor) and the bias was correct. With the crystal mike it allowed the bias to drift up and put the tube into saturation and killed the audio. 73 Gary K4FMX > -----Original Message----- > From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of John > Coleman > Sent: Monday, January 12, 2015 3:33 PM > To: 'John Neeley'; amradio at mailman.qth.net > Subject: Re: [AMRadio] Kenwood MC-50 mike with AM gear > > Hi John, A lot of the old rigs did not even have a coupling capacitor to > the > grid of the preamp stage. This is of no consequence when using a > crystal/ceramic microphone, but other mics may drain your grid bias on > the > preamp tube and cause a lot of distortion. If the coupling cap is not > there > put one in. .01 to .05 is good. Also a lot of the modern microphones > have > way to much bass response for the old rigs modulator and modulation > XFMR. A > coupling capacitor in series with the microphone cable and a resistor > across > the cable on the rig side of the coupling capacitor will reduce the low > frequency response. Start with a .05 uf and 100K resistor. Decreasing > the > value of either will reduce low frequency output and vice versa. Don't > worry about matching impedance. The 1 or 2 meg resistor at the preamp > grid > is there for what is known as contact bias. And it works well with the > crystal/ceramic microphone as they actually have their best response > with > no load or very high resistance. > > Good Luck, > John, WA5BXO > > -----Original Message----- > From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of John > Neeley > Sent: Tuesday, January 06, 2015 11:25 AM > To: amradio at mailman.qth.net > Subject: [AMRadio] Kenwood MC-50 mike with AM gear > > I have a Kenwood MC-50 mike and am wondering if I can use it with my > older, > tube type AM gear, like the HT-32a, Valiant or DX-100? Otherwise if > not, > will need to get a old D-104, etc. Any info would be greatly > appreciated. > > John W6ZKH > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: > http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the > word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html From amradio at mailman.qth.net Mon Jan 12 23:19:36 2015 From: amradio at mailman.qth.net (CL in NC via AMRadio) Date: Mon, 12 Jan 2015 20:19:36 -0800 Subject: [AMRadio] 30S-1 and AM Message-ID: <1421122776.39799.YahooMailBasic@web160605.mail.bf1.yahoo.com> It takes a linear amplifier to amplify AM and this amp qualifies. It is rated at 1KW input power, CW has a 50% duty cycle, and takes 60-100 watts to drive to full output. You won't be able to run it at the AM current legal limit on output power of 350 watts, but you should be able to load it up to 350 watts input and expect around 200+ watts out for 800 or so watts peak output. Please use a scope to set you modulation though. Charlie, W4MEC in NC From amradio at mailman.qth.net Tue Jan 13 06:39:39 2015 From: amradio at mailman.qth.net (Collin via AMRadio) Date: Tue, 13 Jan 2015 06:39:39 -0500 Subject: [AMRadio] Using an old Collins amp for AM In-Reply-To: <54B464D1.4020206@wildblue.net> References: <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> <54B464D1.4020206@wildblue.net> Message-ID: The 32V-2 is what I use most of the time on the AM nets with very good reports. Thank You, Collin > On Jan 12, 2015, at 19:20, wa9vrh wrote: > > Hi Frank, > Have you tried using the 32V-2 on AM. For the Collins Collectors 1st Wednesday > AM net I have been using an Elmac AF-68 which runs less power than > your 32V-2. Might give the 32V-2 a try. > 73 Larry WA9VRH > >> On 1/12/2015 6:09 PM, FRANK HUGHES hughes wrote: >> Hi, >> I would like to be able to participate in some of the AM nets. >> My 32V-2 only makes 70 watts of carrier. (low voltage selected) >> I have a good condition Collins 30S-1 that I normally use for SSB. >> If the power is kept down to about 150 watts of carrier, could I drive the amp w/ the 32V-2? >> >> >> My first homebrew amp is under construction, but until it is ready, I am hoping to find a temporary >> solution. >> 73 >> Frank >> KJ4OLL >> ______________________________________________________________ >> Our Main Website: http://www.amfone.net >> AMRadio mailing list >> Archives: http://mailman.qth.net/pipermail/amradio/ >> List Rules (must read!): http://w5ami.net/amradiofaq.html >> List Home: http://mailman.qth.net/mailman/listinfo/amradio >> Post: AMRadio at mailman.qth.net >> To unsubscribe, send an email to amradio-request at mailman.qth.net with >> the word unsubscribe in the message body. >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> > > From solarelectricjohn at gmail.com Tue Jan 13 07:30:00 2015 From: solarelectricjohn at gmail.com (john nelson) Date: Tue, 13 Jan 2015 06:30:00 -0600 Subject: [AMRadio] Amp Message-ID: Good Morning all, I have been looking for a set of plans to build a 500W to 1kw AM linear amp. I would like to build something that I still can find parts without to much looking. If anyone has an old amp that can be restored or has some parts and plans that would also be great. I have built many SSB amps but want to have a nice AM amp for the shack. I would be exciting it with a viking ranger. Thanks, John WOXAZ From tvman1954 at gmail.com Tue Jan 13 07:32:23 2015 From: tvman1954 at gmail.com (Wade Staggs) Date: Tue, 13 Jan 2015 06:32:23 -0600 Subject: [AMRadio] AMRadio Digest, Vol 132, Issue 7 In-Reply-To: References: Message-ID: *Good Morning All,* * Well, it's the first 500 Watts that makes the difference! If I had a Nickel for every time we have heard that. Unfortunately I don't own a Heavy ( Big ) Iron and Plate Modulated Transmitter ... NOW ..Although I have owned several in the past. All we have to run on AM is the Ten Tec Jupiter and my Heathkit SB-220 Amplifier. When the band is quiet, we can get away with a 20 Watt Carrier and then the PEP Output is about 100 Watts. When using the SB-220 Amp, that 20 Watts of drive nets me about 180 to 200 Watts of Carrier and then the Properly Modulated Envelope says that the PEP Output is about 1000 to 1100 Watts. Even when we get the Heathkit TX-1 Scratchy Apache restored. I don't believe it should be operated with much over about 25 to 30 Watts Carrier. Everybody in the AM Window tells me that I have a Great Signal and Great Audio. Please, tell me which AM Transmitter will do a 100 to 150 Watt Carrier and still have the Headroom to sound good when fully modulated. Am I missing something here? Two 6146 tubes at 150 Watts Carrier would need to Output 600 Watts PEP when 100% Modulated.... And I would like to see someone do this and not Kill the Tubes and or the Power Supply. Yes, I am an Old Timer but still young for a Ham at 60 years old. Please, tell me what Collins Transmitter using 6146 tubes which can output a 150 Watt Carrier and 600 Watts PEP overall and Not Melt Down like the Witch in Wizard of Oz when drenched with water? Could somebody please answer this question? This is an honest question guys because we have never been well off enough to own Collins gear. I can however tell you what would happen if we tried this with the FLdx400 Transmitter, TX-1 Scratchy Apache and can you imagine how quickly the Glass would ... Suck into itself with the sweep tubes in my Yaesu FT-101E? And I don't want to even think about what would happen to my SB-200 at 600 Watts Carrier or the SB-220 at 1 KW Carrier. Well, the 3-500ZG tubes in the SB-220 might last a while but the Power Supply probably wouldn't.* * 73 and May God Bless from Wade/KJ4WS* On Tue, Jan 13, 2015 at 5:39 AM, wrote: > Send AMRadio mailing list submissions to > amradio at mailman.qth.net > > To subscribe or unsubscribe via the World Wide Web, visit > http://mailman.qth.net/mailman/listinfo/amradio > or, via email, send a message with subject or body 'help' to > amradio-request at mailman.qth.net > > You can reach the person managing the list at > amradio-owner at mailman.qth.net > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of AMRadio digest..." > > > Today's Topics: > > 1. Re: Using an old Collins amp for AM (Rob Atkinson) > 2. Re: Using an old Collins amp for AM (Meir WF2U) > 3. Re: Using an old Collins amp for AM (Paul Baldock) > 4. Re: Kenwood MC-50 mike with AM gear (Gary Schafer) > 5. 30S-1 and AM (CL in NC via AMRadio) > 6. Re: Using an old Collins amp for AM (Collin via AMRadio) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Mon, 12 Jan 2015 18:42:18 -0600 > From: Rob Atkinson > To: FRANK HUGHES hughes > Cc: Discussion of AM Radio in the Amateur Service > > Subject: Re: [AMRadio] Using an old Collins amp for AM > Message-ID: > < > CALWD7Z5kvYpocUteygL+68wO6hsk5WTee3X74w5ZEOo5HU_bhw at mail.gmail.com> > Content-Type: text/plain; charset=ISO-8859-1 > > Just run the collins rig into the antenna. It should put out at least > 100 w. You might need to change the 4D32. > > 73 > > Rob > K5UJ > > On Mon, Jan 12, 2015 at 6:09 PM, FRANK HUGHES > hughes wrote: > > Hi, > > I would like to be able to participate in some of the AM nets. > > My 32V-2 only makes 70 watts of carrier. (low voltage selected) > > I have a good condition Collins 30S-1 that I normally use for SSB. > > If the power is kept down to about 150 watts of carrier, could I drive > the amp w/ the 32V-2? > > > > > ------------------------------ > > Message: 2 > Date: Mon, 12 Jan 2015 20:10:30 -0500 > From: "Meir WF2U" > To: "'FRANK HUGHES hughes'" > , > Subject: Re: [AMRadio] Using an old Collins amp for AM > Message-ID: <6F7CCCE6C3CC440EBF95011F96C7DAE9 at MBDCONSULTING.LOCAL> > Content-Type: text/plain; charset="us-ascii" > > Raising the carrier from 70W to 150W means about gaining 1/2 of an S-point > on the receiving end. 1 S-point is 6 dB increase in power, which is > quadrupling it, as if you increased from 70 to 280 W carrier. Doubling the > power is 3 dB, which is a half S-point. > It's not worth the effort. > > 73, Meir WF2U > Landrum, SC > > -----Original Message----- > From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of FRANK > HUGHES hughes > Sent: Monday, January 12, 2015 7:10 PM > To: amradio at mailman.qth.net > Subject: [AMRadio] Using an old Collins amp for AM > > Hi, > I would like to be able to participate in some of the AM nets. > My 32V-2 only makes 70 watts of carrier. (low voltage selected) > I have a good condition Collins 30S-1 that I normally use for SSB. > If the power is kept down to about 150 watts of carrier, could I drive the > amp w/ the 32V-2? > > > My first homebrew amp is under construction, but until it is ready, I am > hoping to find a temporary > solution. > 73 > Frank > KJ4OLL > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > > > ------------------------------ > > Message: 3 > Date: Mon, 12 Jan 2015 17:42:21 -0800 > From: Paul Baldock > To: amradio at mailman.qth.net > Subject: Re: [AMRadio] Using an old Collins amp for AM > Message-ID: > Content-Type: text/plain; charset="us-ascii"; format=flowed > > It's definitely worth the effort, 3dB is very significant for a > marginal signal. However with your 30S1 you should be able to easily > get 250W carrier and 1000W PEP which is 5.5dB more than your 70W. If > you have modified your 30S1 for higher screen voltage, then you can > get 1500W PEP and 375W carrier which is legal limit in the USA. > > You will only need 30W or so of carrier drive for, so for best > modulation characteristics you should put an attenuator between the > the driver rig and the 30S1 and then tune the driver for 70W (or 100W > if that really is the spec). > > Don't forge to tune the linear for maximum PEP and NOT for maximum > carrier. The carrier level should be 25% of the PEP. > > - Paul KW7Y > > > At 05:10 PM 1/12/2015, you wrote: > >Raising the carrier from 70W to 150W means about gaining 1/2 of an S-point > >on the receiving end. 1 S-point is 6 dB increase in power, which is > >quadrupling it, as if you increased from 70 to 280 W carrier. Doubling the > >power is 3 dB, which is a half S-point. > >It's not worth the effort. > > > >73, Meir WF2U > >Landrum, SC > > > >-----Original Message----- > >From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of FRANK > >HUGHES hughes > >Sent: Monday, January 12, 2015 7:10 PM > >To: amradio at mailman.qth.net > >Subject: [AMRadio] Using an old Collins amp for AM > > > >Hi, > >I would like to be able to participate in some of the AM nets. > >My 32V-2 only makes 70 watts of carrier. (low voltage selected) > >I have a good condition Collins 30S-1 that I normally use for SSB. > >If the power is kept down to about 150 watts of carrier, could I drive the > >amp w/ the 32V-2? > > > > > >My first homebrew amp is under construction, but until it is ready, I am > >hoping to find a temporary > >solution. > >73 > >Frank > >KJ4OLL > >______________________________________________________________ > >Our Main Website: http://www.amfone.net > >AMRadio mailing list > >Archives: http://mailman.qth.net/pipermail/amradio/ > >List Rules (must read!): http://w5ami.net/amradiofaq.html > >List Home: http://mailman.qth.net/mailman/listinfo/amradio > >Post: AMRadio at mailman.qth.net > >To unsubscribe, send an email to amradio-request at mailman.qth.net with > >the word unsubscribe in the message body. > > > >This list hosted by: http://www.qsl.net > >Please help support this email list: http://www.qsl.net/donate.html > > > >______________________________________________________________ > >Our Main Website: http://www.amfone.net > >AMRadio mailing list > >Archives: http://mailman.qth.net/pipermail/amradio/ > >List Rules (must read!): http://w5ami.net/amradiofaq.html > >List Home: http://mailman.qth.net/mailman/listinfo/amradio > >Post: AMRadio at mailman.qth.net > >To unsubscribe, send an email to amradio-request at mailman.qth.net with > >the word unsubscribe in the message body. > > > >This list hosted by: http://www.qsl.net > >Please help support this email list: http://www.qsl.net/donate.html > > > --- > This email has been checked for viruses by Avast antivirus software. > http://www.avast.com > > > > ------------------------------ > > Message: 4 > Date: Mon, 12 Jan 2015 21:41:27 -0600 > From: "Gary Schafer" > To: "'John Coleman'" , "'John Neeley'" > , > Subject: Re: [AMRadio] Kenwood MC-50 mike with AM gear > Message-ID: > Content-Type: text/plain; charset="us-ascii" > > Hello John, > > A little story about mikes. A long time ago I had a heath SB100 transceiver > that I had a dynamic mike hooked to. The mike had a transformer in it. > Everything worked fine. > I decided to hook up a D104 crystal mike to the rig. It had low and > distorted audio. I went to the radio store and got a new element for the > D104, same thing. Took the element back for another one and it was the > same. > I finally swapped out the first audio tube and everything worked great. > Turns out that the first audio tube (6U8 I think) had grid leakage. With > the > transformer mike it held the grid at ground (the grid was direct connected > to the mike jack thru a resistor) and the bias was correct. > With the crystal mike it allowed the bias to drift up and put the tube into > saturation and killed the audio. > > 73 > Gary K4FMX > > > -----Original Message----- > > From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of John > > Coleman > > Sent: Monday, January 12, 2015 3:33 PM > > To: 'John Neeley'; amradio at mailman.qth.net > > Subject: Re: [AMRadio] Kenwood MC-50 mike with AM gear > > > > Hi John, A lot of the old rigs did not even have a coupling capacitor to > > the > > grid of the preamp stage. This is of no consequence when using a > > crystal/ceramic microphone, but other mics may drain your grid bias on > > the > > preamp tube and cause a lot of distortion. If the coupling cap is not > > there > > put one in. .01 to .05 is good. Also a lot of the modern microphones > > have > > way to much bass response for the old rigs modulator and modulation > > XFMR. A > > coupling capacitor in series with the microphone cable and a resistor > > across > > the cable on the rig side of the coupling capacitor will reduce the low > > frequency response. Start with a .05 uf and 100K resistor. Decreasing > > the > > value of either will reduce low frequency output and vice versa. Don't > > worry about matching impedance. The 1 or 2 meg resistor at the preamp > > grid > > is there for what is known as contact bias. And it works well with the > > crystal/ceramic microphone as they actually have their best response > > with > > no load or very high resistance. > > > > Good Luck, > > John, WA5BXO > > > > -----Original Message----- > > From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of John > > Neeley > > Sent: Tuesday, January 06, 2015 11:25 AM > > To: amradio at mailman.qth.net > > Subject: [AMRadio] Kenwood MC-50 mike with AM gear > > > > I have a Kenwood MC-50 mike and am wondering if I can use it with my > > older, > > tube type AM gear, like the HT-32a, Valiant or DX-100? Otherwise if > > not, > > will need to get a old D-104, etc. Any info would be greatly > > appreciated. > > > > John W6ZKH > > ______________________________________________________________ > > Our Main Website: http://www.amfone.net > > AMRadio mailing list > > Archives: http://mailman.qth.net/pipermail/amradio/ > > List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: > > http://mailman.qth.net/mailman/listinfo/amradio > > Post: AMRadio at mailman.qth.net > > To unsubscribe, send an email to amradio-request at mailman.qth.net with > > the > > word unsubscribe in the message body. > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > > > ______________________________________________________________ > > Our Main Website: http://www.amfone.net > > AMRadio mailing list > > Archives: http://mailman.qth.net/pipermail/amradio/ > > List Rules (must read!): http://w5ami.net/amradiofaq.html > > List Home: http://mailman.qth.net/mailman/listinfo/amradio > > Post: AMRadio at mailman.qth.net > > To unsubscribe, send an email to amradio-request at mailman.qth.net with > > the word unsubscribe in the message body. > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > > > ------------------------------ > > Message: 5 > Date: Mon, 12 Jan 2015 20:19:36 -0800 > From: CL in NC via AMRadio > To: amradio at mailman.qth.net > Subject: [AMRadio] 30S-1 and AM > Message-ID: > <1421122776.39799.YahooMailBasic at web160605.mail.bf1.yahoo.com> > Content-Type: text/plain; charset=us-ascii > > It takes a linear amplifier to amplify AM and this amp qualifies. It is > rated at 1KW input power, CW has a 50% duty cycle, and takes 60-100 watts > to drive to full output. You won't be able to run it at the AM current > legal limit on output power of 350 watts, but you should be able to load it > up to 350 watts input and expect around 200+ watts out for 800 or so watts > peak output. Please use a scope to set you modulation though. > > Charlie, W4MEC in NC > > > ------------------------------ > > Message: 6 > Date: Tue, 13 Jan 2015 06:39:39 -0500 > From: Collin via AMRadio > To: AM Radio Reflector > Subject: Re: [AMRadio] Using an old Collins amp for AM > Message-ID: > Content-Type: text/plain; charset=us-ascii > > The 32V-2 is what I use most of the time on the AM nets with very good > reports. > > Thank You, Collin > > > On Jan 12, 2015, at 19:20, wa9vrh wrote: > > > > Hi Frank, > > Have you tried using the 32V-2 on AM. For the Collins Collectors 1st > Wednesday > > AM net I have been using an Elmac AF-68 which runs less power than > > your 32V-2. Might give the 32V-2 a try. > > 73 Larry WA9VRH > > > >> On 1/12/2015 6:09 PM, FRANK HUGHES hughes wrote: > >> Hi, > >> I would like to be able to participate in some of the AM nets. > >> My 32V-2 only makes 70 watts of carrier. (low voltage selected) > >> I have a good condition Collins 30S-1 that I normally use for SSB. > >> If the power is kept down to about 150 watts of carrier, could I drive > the amp w/ the 32V-2? > >> > >> > >> My first homebrew amp is under construction, but until it is ready, I > am hoping to find a temporary > >> solution. > >> 73 > >> Frank > >> KJ4OLL > >> ______________________________________________________________ > >> Our Main Website: http://www.amfone.net > >> AMRadio mailing list > >> Archives: http://mailman.qth.net/pipermail/amradio/ > >> List Rules (must read!): http://w5ami.net/amradiofaq.html > >> List Home: http://mailman.qth.net/mailman/listinfo/amradio > >> Post: AMRadio at mailman.qth.net > >> To unsubscribe, send an email to amradio-request at mailman.qth.net with > >> the word unsubscribe in the message body. > >> > >> This list hosted by: http://www.qsl.net > >> Please help support this email list: http://www.qsl.net/donate.html > >> > > > > > > > ------------------------------ > > Subject: Digest Footer > > ______________________________________________________________ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio at mailman.qth.net > > > ------------------------------ > > End of AMRadio Digest, Vol 132, Issue 7 > *************************************** > From tvman1954 at gmail.com Tue Jan 13 07:41:19 2015 From: tvman1954 at gmail.com (Wade Staggs) Date: Tue, 13 Jan 2015 06:41:19 -0600 Subject: [AMRadio] AMRadio Digest, Vol 132, Issue 7 In-Reply-To: References: Message-ID: *Sorry Guys,* * I just realized that he is talking about running a Collins 30S-1 Amplifier at about 150 Watts Carrier....... Please, forgive my rant. * * 73 from Wade/KJ4WS* On Tue, Jan 13, 2015 at 5:39 AM, wrote: > Send AMRadio mailing list submissions to > amradio at mailman.qth.net > > To subscribe or unsubscribe via the World Wide Web, visit > http://mailman.qth.net/mailman/listinfo/amradio > or, via email, send a message with subject or body 'help' to > amradio-request at mailman.qth.net > > You can reach the person managing the list at > amradio-owner at mailman.qth.net > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of AMRadio digest..." > > > Today's Topics: > > 1. Re: Using an old Collins amp for AM (Rob Atkinson) > 2. Re: Using an old Collins amp for AM (Meir WF2U) > 3. Re: Using an old Collins amp for AM (Paul Baldock) > 4. Re: Kenwood MC-50 mike with AM gear (Gary Schafer) > 5. 30S-1 and AM (CL in NC via AMRadio) > 6. Re: Using an old Collins amp for AM (Collin via AMRadio) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Mon, 12 Jan 2015 18:42:18 -0600 > From: Rob Atkinson > To: FRANK HUGHES hughes > Cc: Discussion of AM Radio in the Amateur Service > > Subject: Re: [AMRadio] Using an old Collins amp for AM > Message-ID: > < > CALWD7Z5kvYpocUteygL+68wO6hsk5WTee3X74w5ZEOo5HU_bhw at mail.gmail.com> > Content-Type: text/plain; charset=ISO-8859-1 > > Just run the collins rig into the antenna. It should put out at least > 100 w. You might need to change the 4D32. > > 73 > > Rob > K5UJ > > On Mon, Jan 12, 2015 at 6:09 PM, FRANK HUGHES > hughes wrote: > > Hi, > > I would like to be able to participate in some of the AM nets. > > My 32V-2 only makes 70 watts of carrier. (low voltage selected) > > I have a good condition Collins 30S-1 that I normally use for SSB. > > If the power is kept down to about 150 watts of carrier, could I drive > the amp w/ the 32V-2? > > > > > ------------------------------ > > Message: 2 > Date: Mon, 12 Jan 2015 20:10:30 -0500 > From: "Meir WF2U" > To: "'FRANK HUGHES hughes'" > , > Subject: Re: [AMRadio] Using an old Collins amp for AM > Message-ID: <6F7CCCE6C3CC440EBF95011F96C7DAE9 at MBDCONSULTING.LOCAL> > Content-Type: text/plain; charset="us-ascii" > > Raising the carrier from 70W to 150W means about gaining 1/2 of an S-point > on the receiving end. 1 S-point is 6 dB increase in power, which is > quadrupling it, as if you increased from 70 to 280 W carrier. Doubling the > power is 3 dB, which is a half S-point. > It's not worth the effort. > > 73, Meir WF2U > Landrum, SC > > -----Original Message----- > From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of FRANK > HUGHES hughes > Sent: Monday, January 12, 2015 7:10 PM > To: amradio at mailman.qth.net > Subject: [AMRadio] Using an old Collins amp for AM > > Hi, > I would like to be able to participate in some of the AM nets. > My 32V-2 only makes 70 watts of carrier. (low voltage selected) > I have a good condition Collins 30S-1 that I normally use for SSB. > If the power is kept down to about 150 watts of carrier, could I drive the > amp w/ the 32V-2? > > > My first homebrew amp is under construction, but until it is ready, I am > hoping to find a temporary > solution. > 73 > Frank > KJ4OLL > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > > > ------------------------------ > > Message: 3 > Date: Mon, 12 Jan 2015 17:42:21 -0800 > From: Paul Baldock > To: amradio at mailman.qth.net > Subject: Re: [AMRadio] Using an old Collins amp for AM > Message-ID: > Content-Type: text/plain; charset="us-ascii"; format=flowed > > It's definitely worth the effort, 3dB is very significant for a > marginal signal. However with your 30S1 you should be able to easily > get 250W carrier and 1000W PEP which is 5.5dB more than your 70W. If > you have modified your 30S1 for higher screen voltage, then you can > get 1500W PEP and 375W carrier which is legal limit in the USA. > > You will only need 30W or so of carrier drive for, so for best > modulation characteristics you should put an attenuator between the > the driver rig and the 30S1 and then tune the driver for 70W (or 100W > if that really is the spec). > > Don't forge to tune the linear for maximum PEP and NOT for maximum > carrier. The carrier level should be 25% of the PEP. > > - Paul KW7Y > > > At 05:10 PM 1/12/2015, you wrote: > >Raising the carrier from 70W to 150W means about gaining 1/2 of an S-point > >on the receiving end. 1 S-point is 6 dB increase in power, which is > >quadrupling it, as if you increased from 70 to 280 W carrier. Doubling the > >power is 3 dB, which is a half S-point. > >It's not worth the effort. > > > >73, Meir WF2U > >Landrum, SC > > > >-----Original Message----- > >From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of FRANK > >HUGHES hughes > >Sent: Monday, January 12, 2015 7:10 PM > >To: amradio at mailman.qth.net > >Subject: [AMRadio] Using an old Collins amp for AM > > > >Hi, > >I would like to be able to participate in some of the AM nets. > >My 32V-2 only makes 70 watts of carrier. (low voltage selected) > >I have a good condition Collins 30S-1 that I normally use for SSB. > >If the power is kept down to about 150 watts of carrier, could I drive the > >amp w/ the 32V-2? > > > > > >My first homebrew amp is under construction, but until it is ready, I am > >hoping to find a temporary > >solution. > >73 > >Frank > >KJ4OLL > >______________________________________________________________ > >Our Main Website: http://www.amfone.net > >AMRadio mailing list > >Archives: http://mailman.qth.net/pipermail/amradio/ > >List Rules (must read!): http://w5ami.net/amradiofaq.html > >List Home: http://mailman.qth.net/mailman/listinfo/amradio > >Post: AMRadio at mailman.qth.net > >To unsubscribe, send an email to amradio-request at mailman.qth.net with > >the word unsubscribe in the message body. > > > >This list hosted by: http://www.qsl.net > >Please help support this email list: http://www.qsl.net/donate.html > > > >______________________________________________________________ > >Our Main Website: http://www.amfone.net > >AMRadio mailing list > >Archives: http://mailman.qth.net/pipermail/amradio/ > >List Rules (must read!): http://w5ami.net/amradiofaq.html > >List Home: http://mailman.qth.net/mailman/listinfo/amradio > >Post: AMRadio at mailman.qth.net > >To unsubscribe, send an email to amradio-request at mailman.qth.net with > >the word unsubscribe in the message body. > > > >This list hosted by: http://www.qsl.net > >Please help support this email list: http://www.qsl.net/donate.html > > > --- > This email has been checked for viruses by Avast antivirus software. > http://www.avast.com > > > > ------------------------------ > > Message: 4 > Date: Mon, 12 Jan 2015 21:41:27 -0600 > From: "Gary Schafer" > To: "'John Coleman'" , "'John Neeley'" > , > Subject: Re: [AMRadio] Kenwood MC-50 mike with AM gear > Message-ID: > Content-Type: text/plain; charset="us-ascii" > > Hello John, > > A little story about mikes. A long time ago I had a heath SB100 transceiver > that I had a dynamic mike hooked to. The mike had a transformer in it. > Everything worked fine. > I decided to hook up a D104 crystal mike to the rig. It had low and > distorted audio. I went to the radio store and got a new element for the > D104, same thing. Took the element back for another one and it was the > same. > I finally swapped out the first audio tube and everything worked great. > Turns out that the first audio tube (6U8 I think) had grid leakage. With > the > transformer mike it held the grid at ground (the grid was direct connected > to the mike jack thru a resistor) and the bias was correct. > With the crystal mike it allowed the bias to drift up and put the tube into > saturation and killed the audio. > > 73 > Gary K4FMX > > > -----Original Message----- > > From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of John > > Coleman > > Sent: Monday, January 12, 2015 3:33 PM > > To: 'John Neeley'; amradio at mailman.qth.net > > Subject: Re: [AMRadio] Kenwood MC-50 mike with AM gear > > > > Hi John, A lot of the old rigs did not even have a coupling capacitor to > > the > > grid of the preamp stage. This is of no consequence when using a > > crystal/ceramic microphone, but other mics may drain your grid bias on > > the > > preamp tube and cause a lot of distortion. If the coupling cap is not > > there > > put one in. .01 to .05 is good. Also a lot of the modern microphones > > have > > way to much bass response for the old rigs modulator and modulation > > XFMR. A > > coupling capacitor in series with the microphone cable and a resistor > > across > > the cable on the rig side of the coupling capacitor will reduce the low > > frequency response. Start with a .05 uf and 100K resistor. Decreasing > > the > > value of either will reduce low frequency output and vice versa. Don't > > worry about matching impedance. The 1 or 2 meg resistor at the preamp > > grid > > is there for what is known as contact bias. And it works well with the > > crystal/ceramic microphone as they actually have their best response > > with > > no load or very high resistance. > > > > Good Luck, > > John, WA5BXO > > > > -----Original Message----- > > From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of John > > Neeley > > Sent: Tuesday, January 06, 2015 11:25 AM > > To: amradio at mailman.qth.net > > Subject: [AMRadio] Kenwood MC-50 mike with AM gear > > > > I have a Kenwood MC-50 mike and am wondering if I can use it with my > > older, > > tube type AM gear, like the HT-32a, Valiant or DX-100? Otherwise if > > not, > > will need to get a old D-104, etc. Any info would be greatly > > appreciated. > > > > John W6ZKH > > ______________________________________________________________ > > Our Main Website: http://www.amfone.net > > AMRadio mailing list > > Archives: http://mailman.qth.net/pipermail/amradio/ > > List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: > > http://mailman.qth.net/mailman/listinfo/amradio > > Post: AMRadio at mailman.qth.net > > To unsubscribe, send an email to amradio-request at mailman.qth.net with > > the > > word unsubscribe in the message body. > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > > > ______________________________________________________________ > > Our Main Website: http://www.amfone.net > > AMRadio mailing list > > Archives: http://mailman.qth.net/pipermail/amradio/ > > List Rules (must read!): http://w5ami.net/amradiofaq.html > > List Home: http://mailman.qth.net/mailman/listinfo/amradio > > Post: AMRadio at mailman.qth.net > > To unsubscribe, send an email to amradio-request at mailman.qth.net with > > the word unsubscribe in the message body. > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > > > ------------------------------ > > Message: 5 > Date: Mon, 12 Jan 2015 20:19:36 -0800 > From: CL in NC via AMRadio > To: amradio at mailman.qth.net > Subject: [AMRadio] 30S-1 and AM > Message-ID: > <1421122776.39799.YahooMailBasic at web160605.mail.bf1.yahoo.com> > Content-Type: text/plain; charset=us-ascii > > It takes a linear amplifier to amplify AM and this amp qualifies. It is > rated at 1KW input power, CW has a 50% duty cycle, and takes 60-100 watts > to drive to full output. You won't be able to run it at the AM current > legal limit on output power of 350 watts, but you should be able to load it > up to 350 watts input and expect around 200+ watts out for 800 or so watts > peak output. Please use a scope to set you modulation though. > > Charlie, W4MEC in NC > > > ------------------------------ > > Message: 6 > Date: Tue, 13 Jan 2015 06:39:39 -0500 > From: Collin via AMRadio > To: AM Radio Reflector > Subject: Re: [AMRadio] Using an old Collins amp for AM > Message-ID: > Content-Type: text/plain; charset=us-ascii > > The 32V-2 is what I use most of the time on the AM nets with very good > reports. > > Thank You, Collin > > > On Jan 12, 2015, at 19:20, wa9vrh wrote: > > > > Hi Frank, > > Have you tried using the 32V-2 on AM. For the Collins Collectors 1st > Wednesday > > AM net I have been using an Elmac AF-68 which runs less power than > > your 32V-2. Might give the 32V-2 a try. > > 73 Larry WA9VRH > > > >> On 1/12/2015 6:09 PM, FRANK HUGHES hughes wrote: > >> Hi, > >> I would like to be able to participate in some of the AM nets. > >> My 32V-2 only makes 70 watts of carrier. (low voltage selected) > >> I have a good condition Collins 30S-1 that I normally use for SSB. > >> If the power is kept down to about 150 watts of carrier, could I drive > the amp w/ the 32V-2? > >> > >> > >> My first homebrew amp is under construction, but until it is ready, I > am hoping to find a temporary > >> solution. > >> 73 > >> Frank > >> KJ4OLL > >> ______________________________________________________________ > >> Our Main Website: http://www.amfone.net > >> AMRadio mailing list > >> Archives: http://mailman.qth.net/pipermail/amradio/ > >> List Rules (must read!): http://w5ami.net/amradiofaq.html > >> List Home: http://mailman.qth.net/mailman/listinfo/amradio > >> Post: AMRadio at mailman.qth.net > >> To unsubscribe, send an email to amradio-request at mailman.qth.net with > >> the word unsubscribe in the message body. > >> > >> This list hosted by: http://www.qsl.net > >> Please help support this email list: http://www.qsl.net/donate.html > >> > > > > > > > ------------------------------ > > Subject: Digest Footer > > ______________________________________________________________ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio at mailman.qth.net > > > ------------------------------ > > End of AMRadio Digest, Vol 132, Issue 7 > *************************************** > From rbethman at comcast.net Tue Jan 13 07:55:08 2015 From: rbethman at comcast.net (rbethman) Date: Tue, 13 Jan 2015 07:55:08 -0500 Subject: [AMRadio] AMRadio Rigs and amps. In-Reply-To: References: Message-ID: <54B515AC.9070904@comcast.net> Wade, The Scratchy Apache will hold 100W carrier and 400W Modulated output. It will do it without melting anything! Putting an amp behind it is pretty much impossible unless you go for a pair of 4-1000s. Then you'll be way over legal limits. I don't run BIG IRON AM any longer. This 64 year old body can't move a BC-610 around any longer. Although it did 400W carrier, and I won't go into what the modulated output was. A few hundred watts output will get you heard. Those that claim they can't hear you simply have the RF Gain dialed such that it takes a KW+ to be heard. Don't pay them any mind! I use a 25W signal into a pair of 3-500Zs. I talk to plenty of folks. I sit here in VA, and talk to Illinois, West Virginia, PA, and down into South Carolina. Those that really want a QSO will get in and talk to anyone they can hear. That's all one needs! It *is* about communicating, not splattering! Regards, Bob - N0DGN On 1/13/2015 7:32 AM, Wade Staggs wrote: > *Good Morning All,* > * Well, it's the first 500 Watts that > makes the difference! If I had a Nickel for every time we have heard that. > Unfortunately I don't own a Heavy ( Big ) Iron and Plate Modulated > Transmitter ... NOW ..Although I have owned several in the past. All we > have to run on AM is the Ten Tec Jupiter and my Heathkit SB-220 Amplifier. > When the band is quiet, we can get away with a 20 Watt Carrier and then the > PEP Output is about 100 Watts. When using the SB-220 Amp, that 20 Watts of > drive nets me about 180 to 200 Watts of Carrier and then the Properly > Modulated Envelope says that the PEP Output is about 1000 to 1100 Watts. > Even when we get the Heathkit TX-1 Scratchy Apache restored. I don't > believe it should be operated with much over about 25 to 30 Watts Carrier. > Everybody in the AM Window tells me that I have a Great Signal and Great > Audio. Please, tell me which AM Transmitter will do a 100 to 150 Watt > Carrier and still have the Headroom to sound good when fully modulated. Am > I missing something here? Two 6146 tubes at 150 Watts Carrier would need to > Output 600 Watts PEP when 100% Modulated.... And I would like to see > someone do this and not Kill the Tubes and or the Power Supply. Yes, I am > an Old Timer but still young for a Ham at 60 years old. Please, tell me > what Collins Transmitter using 6146 tubes which can output a 150 Watt > Carrier and 600 Watts PEP overall and Not Melt Down like the Witch in > Wizard of Oz when drenched with water? Could somebody please answer this > question? This is an honest question guys because we have never been well > off enough to own Collins gear. I can however tell you what would happen if > we tried this with the FLdx400 Transmitter, TX-1 Scratchy Apache and can > you imagine how quickly the Glass would ... Suck into itself with the sweep > tubes in my Yaesu FT-101E? And I don't want to even think about what would > happen to my SB-200 at 600 Watts Carrier or the SB-220 at 1 KW Carrier. > Well, the 3-500ZG tubes in the SB-220 might last a while but the Power > Supply probably wouldn't.* > > * 73 and May God Bless from Wade/KJ4WS* -- Bob - N0DGN From ranchorobbo at gmail.com Tue Jan 13 12:56:32 2015 From: ranchorobbo at gmail.com (Rob Atkinson) Date: Tue, 13 Jan 2015 11:56:32 -0600 Subject: [AMRadio] Amp In-Reply-To: References: Message-ID: 4-1000A with 5.5 KV on the plate. put the tube in a chimney; use the plastic socket that lets a lot of air move over the pins and pressurize the chassis with a blower. Doesn't take a loud one to get the job done. rob K5UJ On Tue, Jan 13, 2015 at 6:30 AM, john nelson wrote: > Good Morning all, I have been looking for a set of plans to build a 500W to > 1kw AM linear amp. I would like to build something that I still can find > parts without to much looking. From frsahu0003 at embarqmail.com Tue Jan 13 15:22:04 2015 From: frsahu0003 at embarqmail.com (FRANK HUGHES hughes) Date: Tue, 13 Jan 2015 15:22:04 -0500 (EST) Subject: [AMRadio] 32V-2 driving 30S-1 plan In-Reply-To: <802371968.24724981.1421180513291.JavaMail.root@embarqmail.com> Message-ID: <177964220.24725189.1421180524631.JavaMail.root@embarqmail.com> Hi, Thanks for all the tips and ideas! I can see how the receiving end may not copy any better unless the power is increased by more than 3dB. But I won't know for sure how much I can get out of the 30S-1 w/o distortion unless I try it first. I have a couple of attenuators I can try between the 32V-2 and 30S-1. Have to do some experiments to see what happens. I have a Radio Engineering Associates probe for high power that I can use to see what the signal looks like. 73 Frank KJ4OLL From ranchorobbo at gmail.com Tue Jan 13 19:19:07 2015 From: ranchorobbo at gmail.com (Rob Atkinson) Date: Tue, 13 Jan 2015 18:19:07 -0600 Subject: [AMRadio] 32V-2 driving 30S-1 plan In-Reply-To: <177964220.24725189.1421180524631.JavaMail.root@embarqmail.com> References: <802371968.24724981.1421180513291.JavaMail.root@embarqmail.com> <177964220.24725189.1421180524631.JavaMail.root@embarqmail.com> Message-ID: usually the limitations on an amp designed for slopbucket are cooling and the power supply. for continuous buzzard AM you need plate iron that can comfortably supply twice resting carrier current and you usually have to up the cooling because most commercial mfrs make hammy appliance amps to run with quiet cooling, because ops piss and moan about the fan noise if they make them to run real power continuous. Many hams also piss and moan about any rig that weighs more than 30 pounds so they also make them with lightweight iron to cut down on the weight. Forget about PEP--that's slopbucket power language; run what carrier you can get out of the amp and look at the peaks on a scope--if they aren't flat you are okay. Don't know much about the 30S-1, but as an older design it may be better built. Check the manual spec's to see what Collins set forth on the RF power capability--some mfrs have one claim for SSB/CW and another for RTTY. Or they may have a 10 minute time limit. Anything like that is a clue that you have to study the plate transformer rating for CCS current and look at how the tube is cooled. Keep an eye on things, especially at first--if the carrier power drops after a few minutes, or the line vswr changes, something is probably heating and drifting--might be in the feedline or the amp's output network. Cheap tuners, low pass TV filters, etc. zorch and succumb to AM. 73 Rob K5UJ From ranchorobbo at gmail.com Tue Jan 13 20:16:25 2015 From: ranchorobbo at gmail.com (Rob Atkinson) Date: Tue, 13 Jan 2015 19:16:25 -0600 Subject: [AMRadio] Free BC-1G in Burns OR Message-ID: Link Reed-Nickerson is retiring and cleaning house. He is a broadcast engineer out in Burns OR and has a BC-1G free for hauling. With his permission I am sending his email to the AM list. Rob K5UJ _____________________________________________________________________ I've retired, decided to clean house, and sell this equipment I have in Eastern Oregon. I've got a two-tower AM-19. Kintronic Labs Phasor for a 3-tower DA and 3 ATU's that came from Beverly, MA, were only in service for a couple of years and look like they just rolled off the production line. I was going to repurpose them with the help of Ben Dawson for a 2-tower DA on 1210". To heck with it, I'm retired and living in Australia, I've had enough radio for one life time! 3 - Austin A-4197-L base insulators 800+ feet of 7/8 Heliax (aluminum jacket). A two-bay rototiller for 92.7 with radomes, end fed, 2-bay. 8kw power rating. On ground, replaced with 4 bay. Comrex Bric-link pair, used about a year. Gates BC-1G. That's free to any ham that wants it. Stations are for sale, too! Contact me at lincnickerson at gmail.com. Or call or email ashley at kbnh.am. 541-589-1613 From b.gaz at comcast.net Tue Jan 13 21:24:47 2015 From: b.gaz at comcast.net (b.gaz at comcast.net) Date: Wed, 14 Jan 2015 02:24:47 +0000 (UTC) Subject: [AMRadio] Using an old Collins amp for AM In-Reply-To: References: <1361302373.24255308.1421107794296.JavaMail.root@embarqmail.com> <54B464D1.4020206@wildblue.net> Message-ID: <920570914.704355.1421202287584.JavaMail.zimbra@comcast.net> I run my 32V3 at 700 volts and 200 ma for 100 watts out, and I have KT90 hifi tubes as modulators. Been running that way for 30 years without a single crapout. I solid stated all the rectifiers and the transformers run at room temps. I also use it as an exciter so it spends a lot of time turned on. Mine is not a collectors item, its missing a cabinet and a driver transformer, so I do not worry about its resale value. And 100 watts is good power on 40 meters. Brett N2DTS ----- Original Message ----- From: "Collin via AMRadio" To: "AM Radio Reflector" Sent: Tuesday, January 13, 2015 6:39:39 AM Subject: Re: [AMRadio] Using an old Collins amp for AM The 32V-2 is what I use most of the time on the AM nets with very good reports. Thank You, Collin > On Jan 12, 2015, at 19:20, wa9vrh wrote: > > Hi Frank, > Have you tried using the 32V-2 on AM. For the Collins Collectors 1st Wednesday > AM net I have been using an Elmac AF-68 which runs less power than > your 32V-2. Might give the 32V-2 a try. > 73 Larry WA9VRH > >> On 1/12/2015 6:09 PM, FRANK HUGHES hughes wrote: >> Hi, >> I would like to be able to participate in some of the AM nets. >> My 32V-2 only makes 70 watts of carrier. (low voltage selected) >> I have a good condition Collins 30S-1 that I normally use for SSB. >> If the power is kept down to about 150 watts of carrier, could I drive the amp w/ the 32V-2? >> >> >> My first homebrew amp is under construction, but until it is ready, I am hoping to find a temporary >> solution. >> 73 >> Frank >> KJ4OLL >> ______________________________________________________________ >> Our Main Website: http://www.amfone.net >> AMRadio mailing list >> Archives: http://mailman.qth.net/pipermail/amradio/ >> List Rules (must read!): http://w5ami.net/amradiofaq.html >> List Home: http://mailman.qth.net/mailman/listinfo/amradio >> Post: AMRadio at mailman.qth.net >> To unsubscribe, send an email to amradio-request at mailman.qth.net with >> the word unsubscribe in the message body. >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> > > ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Archives: http://mailman.qth.net/pipermail/amradio/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: AMRadio at mailman.qth.net To unsubscribe, send an email to amradio-request at mailman.qth.net with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html From ars.w5omr at gmail.com Wed Jan 14 21:34:05 2015 From: ars.w5omr at gmail.com (Geoff) Date: Wed, 14 Jan 2015 20:34:05 -0600 Subject: [AMRadio] 30S-1 and AM In-Reply-To: <1421122776.39799.YahooMailBasic@web160605.mail.bf1.yahoo.com> References: <1421122776.39799.YahooMailBasic@web160605.mail.bf1.yahoo.com> Message-ID: <54B7271D.3010404@gmail.com> On 01/12/2015 10:19 PM, CL in NC via AMRadio wrote: > You won't be able to run it at the AM current legal limit on output power of 350 watts, There is no such "legal limit" of 350 watts. http://www.qsl.net/wa5bxo/asyam/aam3.html From Tonne at Comcast.net Wed Jan 14 22:00:53 2015 From: Tonne at Comcast.net (Jim Tonne) Date: Wed, 14 Jan 2015 22:00:53 -0500 Subject: [AMRadio] 30S-1 and AM In-Reply-To: <54B7271D.3010404@gmail.com> References: <1421122776.39799.YahooMailBasic@web160605.mail.bf1.yahoo.com> <54B7271D.3010404@gmail.com> Message-ID: <54B72D65.6080208@Comcast.net> The current legal limit on transmitter output is 1500 watts PEP which is 375 watts at carrier on AM. How that came about borderlines on criminal. - Jim Tonne W4ENE On 1/14/2015 9:34 PM, Geoff wrote: > On 01/12/2015 10:19 PM, CL in NC via AMRadio wrote: >> You won't be able to run it at the AM current legal limit on output power of 350 watts, > There is no such "legal limit" of 350 watts. > > http://www.qsl.net/wa5bxo/asyam/aam3.html > > From ars.w5omr at gmail.com Wed Jan 14 22:27:27 2015 From: ars.w5omr at gmail.com (Geoff) Date: Wed, 14 Jan 2015 21:27:27 -0600 Subject: [AMRadio] 30S-1 and AM In-Reply-To: <54B72D65.6080208@Comcast.net> References: <1421122776.39799.YahooMailBasic@web160605.mail.bf1.yahoo.com> <54B7271D.3010404@gmail.com> <54B72D65.6080208@Comcast.net> Message-ID: <54B7339F.104@gmail.com> On 01/14/2015 09:00 PM, Jim Tonne wrote: > > > > The current legal limit on transmitter output is 1500 watts PEP > which is 375 watts at carrier on AM. It is, if we spoken in sine-wave. We do not, so no, 375w is -not- the legal limit. 1500w PEP output is. Read the link below, please. http://www.qsl.net/wa5bxo/asyam/aam3.html > How that came about borderlines on criminal. On this, we whole heartedly are in complete agreement. From ranchorobbo at gmail.com Thu Jan 15 06:13:20 2015 From: ranchorobbo at gmail.com (Rob Atkinson) Date: Thu, 15 Jan 2015 05:13:20 -0600 Subject: [AMRadio] 30S-1 and AM In-Reply-To: <54B7339F.104@gmail.com> References: <1421122776.39799.YahooMailBasic@web160605.mail.bf1.yahoo.com> <54B7271D.3010404@gmail.com> <54B72D65.6080208@Comcast.net> <54B7339F.104@gmail.com> Message-ID: "375 watts" and "PEP" are ridiculous concepts developed for the modern era of slopbucket/CW linear amps, cheap hammy watt meters and should not be a part of RF power conversations in the realistic AM world in my opinion. No one can precisely measure PEP or "375 watts." Rarely does anyone operate into a 50 J0 load. Let's quit kidding ourselves. Just run whatever carrier you can get out of your rig, modulate it to near 100% negative and move on. The exception is for anyone who has never in his life driven over the speed limit on US highways. If you are one of those types you may go ahead and obsess over the 375 watt nonsense. 73 Rob K5UJ From rbethman at comcast.net Thu Jan 15 07:14:10 2015 From: rbethman at comcast.net (rbethman) Date: Thu, 15 Jan 2015 07:14:10 -0500 Subject: [AMRadio] AM In-Reply-To: References: <1421122776.39799.YahooMailBasic@web160605.mail.bf1.yahoo.com> <54B7271D.3010404@gmail.com> <54B72D65.6080208@Comcast.net> <54B7339F.104@gmail.com> Message-ID: <54B7AF12.1070309@comcast.net> Rob and Geoff have hit it squarely on the head! You can add insult to injury by reading 42CFR Part 97. The 1500W PEP is to be measured "At the input to the antenna.". [Is this the shack end of the feed-line, or is it at the actual junction of feed-line and radiating element?] Now how this is to be achieved, and using *what* to measure it with is left hanging in the air! The amateur community has been brainwashed into the almighty Bird Wattmeter is "the standard". Unless it has been sent in for calibration, AND the elements that go with it, you have no idea whatsoever what you are really reading. The FCC doesn't specify WHAT you are to measure it with. So simply do as Rob has stated, and get on with it. Regards, Bob - N0DGN On 1/15/2015 6:13 AM, Rob Atkinson wrote: > "375 watts" and "PEP" are ridiculous concepts developed for the modern > era of slopbucket/CW linear amps, cheap hammy watt meters and should > not be a part of RF power conversations in the realistic AM world in > my opinion. > > No one can precisely measure PEP or "375 watts." Rarely does anyone > operate into a 50 J0 load. Let's quit kidding ourselves. Just run > whatever carrier you can get out of your rig, modulate it to near 100% > negative and move on. > > The exception is for anyone who has never in his life driven over the > speed limit on US highways. If you are one of those types you may go > ahead and obsess over the 375 watt nonsense. > > 73 > > Rob > K5UJ -- Bob - N0DGN From k9cox at charter.net Thu Jan 15 08:16:14 2015 From: k9cox at charter.net (k9cox at charter.net) Date: Thu, 15 Jan 2015 13:16:14 +0000 Subject: [AMRadio] =?utf-8?q?30S-1_and_AM?= In-Reply-To: References: <1421122776.39799.YahooMailBasic@web160605.mail.bf1.yahoo.com> <54B7271D.3010404@gmail.com> <54B72D65.6080208@Comcast.net> <54B7339F.104@gmail.com>, Message-ID: I removed the tag from my pillow. Sent from Windows Mail From: Rob Atkinson Sent: ?Thursday?, ?January? ?15?, ?2015 ?5?:?13? ?AM To: Discussion of AM Radio in the Amateur Service "375 watts" and "PEP" are ridiculous concepts developed for the modern era of slopbucket/CW linear amps, cheap hammy watt meters and should not be a part of RF power conversations in the realistic AM world in my opinion. No one can precisely measure PEP or "375 watts." Rarely does anyone operate into a 50 J0 load. Let's quit kidding ourselves. Just run whatever carrier you can get out of your rig, modulate it to near 100% negative and move on. The exception is for anyone who has never in his life driven over the speed limit on US highways. If you are one of those types you may go ahead and obsess over the 375 watt nonsense. 73 Rob K5UJ ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Archives: http://mailman.qth.net/pipermail/amradio/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: AMRadio at mailman.qth.net To unsubscribe, send an email to amradio-request at mailman.qth.net with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html From amradio at mailman.qth.net Thu Jan 15 09:35:51 2015 From: amradio at mailman.qth.net (CL in NC via AMRadio) Date: Thu, 15 Jan 2015 06:35:51 -0800 Subject: [AMRadio] 30S-1 and AM Message-ID: <1421332551.84995.YahooMailBasic@web160604.mail.bf1.yahoo.com> Sheeesh...I made a mistake by 25 watts and not calling it 375 watts carrier output. Yes, the ARRL through the FCC screwed us with the 1500 watt PEP rule that translates to approx. 375 watts carrier out, just like they did by forcing the FCC's hand on the code requirement where the FCC got fed up and removed it all. Like everything else lately in the country, there is nothing you can do about it, and the 30-S1 will still only handle about 350 watts input on AM, if that. Charlie, W4MEC in NC From k9cox at charter.net Thu Jan 15 10:11:54 2015 From: k9cox at charter.net (Ross Stenberg) Date: Thu, 15 Jan 2015 09:11:54 -0600 Subject: [AMRadio] 30S-1 and AM In-Reply-To: <1421332551.84995.YahooMailBasic@web160604.mail.bf1.yahoo.com> References: <1421332551.84995.YahooMailBasic@web160604.mail.bf1.yahoo.com> Message-ID: <2D58E63BC40941B88B969663ADB56ED8@RossFlexSDR> As long as we are all being curmudgeons, allow me to add my dirty 2 cents. Watts is really a rather useless measurement in the RF world. The professionals use dBm since it has more relevance. The difference in signal strength between 1 and 2 watts is the same as between 1000 and 2000 watts. 73 Ross K9COX From w5jo at brightok.net Thu Jan 15 10:25:58 2015 From: w5jo at brightok.net (Jim Wilhite) Date: Thu, 15 Jan 2015 09:25:58 -0600 Subject: [AMRadio] Capacitor Message-ID: <2AFB4BA09245405AAF967BFD025E0E9D@JimPC> Does anyone have a 100 pf., 2500 volt Series A2 Mica or the like they would sell me or trade for a 100 pf. 5000 volt F2 series? Space doesn?t allow mounting of the F2 in my application. Jim W5JO From manualman at juno.com Thu Jan 15 13:48:21 2015 From: manualman at juno.com (manualman at juno.com) Date: Thu, 15 Jan 2015 13:48:21 -0500 Subject: [AMRadio] 30S-1 and AM Message-ID: The ARRL had nothing to do with either one of these rules. The ARRL even fought against the removal of the code requirement. Pete, wa2cwa On Thu, 15 Jan 2015 06:35:51 -0800 CL in NC via AMRadio writes: Yes, the ARRL through the FCC screwed us with the 1500 watt PEP rule that translates to approx. 375 watts carrier out, just like they did by forcing the FCC's hand on the code requirement where the FCC got fed up and removed it all. > Charlie, W4MEC in NC > From k4kyv at charter.net Fri Jan 16 01:45:13 2015 From: k4kyv at charter.net (Donald Chester) Date: Fri, 16 Jan 2015 00:45:13 -0600 Subject: [AMRadio] Audio Driver Transformer advice Message-ID: <004801d03157$faf488f0$f0dd9ad0$@charter.net> ----- Original Message ----- >>>>From: Paul Baldock I'm building a modulator with 2 x 813's in pushpull (strapped as triodes) driven by a 20W Solid State audio amplifier. I need a driver transformer to go between the 813 grids and the 20W amp. The 20W amp can drive about 20V peak to peak. I think I need about 200V peak to peak for the 813's, so a 10:1 turns ratio ratio would be about right. So based on that an audio transformer designed to go from 600Ohms center tapped to 4 or 8 ohms would probably do the job. Have I got the math right? Does something like this exist? Thanks Paul >>>>> For best results, use the least amount of step-up possible to just barely get the required peak-to-peak audio voltage, with a little bit of additional head-room. Ideally, the driver amplifier will go into saturation (flat-top) at the same instant that the modulator is driven to its maximum capability. IOW, the driver and modulator stage reach saturation at the same time. I would design in a little extra margin, so that the driver is capable of driving the modulator slightly beyond saturation, just to make sure you get the maximum undistorted audio power out of the modulator before the driver starts clipping. A typical class-B grid impedance varies widely over the audio cycle, from infinite ohms (on the negative half of the cycle when the tube is not conducting, down to a minimum of about 500 ohms at the crest of the positive peak. The grid voltage / grid impedance curve will likely be non-linear. The total impedance of the whole mid-tapped winding would be something like 4 times 500 ohms, or 2000 ohms. Using the 8-ohm tap, the impedance ratio would be 8 ohms to 2000 ohms, or a 1:250 Z ratio. That would be equivalent to a 1 : 15.8 turns ratio. The 4-ohm tap would require more step-up, 1 : 22.7. I doubt that a 600 ohms to 8 ohms transformer would give enough voltage swing. It may be hard to find an output transformer with a primary impedance as low as 2000 ohms at that power level, although I'm sure such a thing exists somewhere. In the real world, I would look for a good quality hi-fi output transformer rated for at least 20 watts, and preferably 30 watts or more, with as low a plate-to-plate impedance on the primary as you can find, but nothing much below 2000 ohms. A (backwards wired) transformer with more step-up will deliver more peak-to-peak voltage to the grid, but the effective internal resistance of the source voltage will be increased, giving more distortion as the audio source voltage regulation is degraded. Putting it another way, using too much step-up, the grids of the tube will cause the audio voltage output from the transformer to sag. Ideally you might find a transformer with multiple taps so you could experiment to find the optimum turns ratio, but you'll have to make do with the best you can find. Also, a transformer rated for higher power (and lower primary impedance) will tend to have lower winding resistance, which would reduce the audio voltage sag. Once you have found what looks like a suitable transformer, try both the 4-ohm and 8-ohm tap and see which one gives the most satisfactory results with the least distortion. Don k4kyv --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com From k4kyv at charter.net Fri Jan 16 02:47:22 2015 From: k4kyv at charter.net (Donald Chester) Date: Fri, 16 Jan 2015 01:47:22 -0600 Subject: [AMRadio] 30S-1 and AM Message-ID: <006e01d03160$a9a700a0$fcf501e0$@charter.net> >>>>>From: Rob Atkinson "375 watts" and "PEP" are ridiculous concepts developed for the modern era of slopbucket/CW linear amps, cheap hammy watt meters and should not be a part of RF power conversations in the realistic AM world in my opinion. No one can precisely measure PEP or "375 watts." Rarely does anyone operate into a 50 J0 load. Let's quit kidding ourselves. Just run whatever carrier you can get out of your rig, modulate it to near 100% negative and move on. The exception is for anyone who has never in his life driven over the speed limit on US highways. If you are one of those types you may go ahead and obsess over the 375 watt nonsense. 73 Rob K5UJ>>>>>> Which brings up another one of my pet peeves. Now, this has nothing to do with the so-called "legal limit", which was always defined in terms of DC input to the final from the very beginning of amateur radio licensing, until Johnny Johnston rammed through his bogus p.e.p. bull Shi'ite, by way of a demonstrably fraudulent proceeding (I have documentation on file), but that's a whole other topic for another day. What I am talking about is how AMers are increasingly describing over the air these days, the power they are running. When talking about AM, "100 watts" is understood to mean 100 watts CARRIER power. WLS and WSM run 50,000 watts... of CARRIER! It really gores my ox whenever I hear some AMer announce how he is running 100 watts and then dutifully add that he is 'peaking up to' 400 watts (or whatever). Let's get out of this slopbucket mind set, and describe our power in AM terms. In other words, CARRIER power! Unless stated otherwise, it is assumed that an AM transmitter is being modulated to 100% or somewhere close to it. If the other fellow is interested in the p.e.p., let him figure that out for himself. The only situation where we have any reason to announce our carrier power, and then add what it's peaking up to, is when we are running controlled carrier, since the carrier increases to a higher level when modulation is present. In that case, you might be running your DX-60 or T4X at 40 watts carrier, and peak up to 75, 100 watts or whatever carrier power those rigs peak up to. Otherwise, when talking AM, let's stay with AM jargon. Don k4kyv --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com From k4kyv at charter.net Fri Jan 16 03:11:54 2015 From: k4kyv at charter.net (Donald Chester) Date: Fri, 16 Jan 2015 02:11:54 -0600 Subject: [AMRadio] AM Message-ID: <007e01d03164$170923f0$451b6bd0$@charter.net> >>>>The amateur community has been brainwashed into the almighty Bird Wattmeter is "the standard". Regards, Bob - N0DGN >>>>> Just as the AM community has been brainwashed into the p.e.p. nonsense. Case in point: " The Scratchy Apache will hold 100W carrier and 400W Modulated output." "Modulated output" my arse. The Apache is a 100-watt transmitter. And I might add, I wouldn't have any use for a Bird Wattmeter even if someone gave me one. There isn't a sprig of coax anywhere in my entire transmitting antenna system, from the plates of the final to the radiating element of the antenna. Everything is tied together with link coupling and balanced open wire line - the real stuff, #8 and #10 copperweld spaced 2 1/2 and 2 inches apart respectively. None of that oversize TV ribbon with the square holes punched in the insulation every few inches. Don k4kyv --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com From cw_de_n5op at sbcglobal.net Fri Jan 16 07:47:33 2015 From: cw_de_n5op at sbcglobal.net (Kim Elmore) Date: Fri, 16 Jan 2015 06:47:33 -0600 Subject: [AMRadio] AM In-Reply-To: <007e01d03164$170923f0$451b6bd0$@charter.net> References: <007e01d03164$170923f0$451b6bd0$@charter.net> Message-ID: AND! You, no doubt, mined, smelted and drew the copper through your home-made dies and made you own ceramic, fired in your own oven! :) Kim N5OP "People that make music together cannot be enemies, at least as long as the music lasts." -- Paul Hindemith On Jan 16, 2015, at 2:11, "Donald Chester" wrote: >>>>> The amateur community has been brainwashed into the almighty Bird > Wattmeter is "the standard". > > Regards, Bob - N0DGN >>>>> > > Just as the AM community has been brainwashed into the p.e.p. nonsense. Case > in point: " The Scratchy Apache will hold 100W carrier and 400W Modulated > output." > > "Modulated output" my arse. The Apache is a 100-watt transmitter. > > > And I might add, I wouldn't have any use for a Bird Wattmeter even if > someone gave me one. There isn't a sprig of coax anywhere in my entire > transmitting antenna system, from the plates of the final to the radiating > element of the antenna. Everything is tied together with link coupling and > balanced open wire line - the real stuff, #8 and #10 copperweld spaced 2 > 1/2 and 2 inches apart respectively. None of that oversize TV ribbon with > the square holes punched in the insulation every few inches. > > > Don k4kyv > > > > --- > This email has been checked for viruses by Avast antivirus software. > http://www.avast.com > > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Archives: http://mailman.qth.net/pipermail/amradio/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio at mailman.qth.net > To unsubscribe, send an email to amradio-request at mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html From paul at paulbaldock.com Fri Jan 16 10:53:49 2015 From: paul at paulbaldock.com (Paul Baldock) Date: Fri, 16 Jan 2015 07:53:49 -0800 Subject: [AMRadio] Audio Driver Transformer advice In-Reply-To: <004801d03157$faf488f0$f0dd9ad0$@charter.net> References: <004801d03157$faf488f0$f0dd9ad0$@charter.net> Message-ID: <54b93412.c20f460a.4521.ffffd71a@mx.google.com> Thanks for your input. I finished up using two step up transformers with the 8 ohms sides in parallel and the 500 Ohm sides in series to simulate a center tap. So that is effectively 8 Ohms to 2000 Ohms, center tapped. Testing in to a 1K resistive load the output looks reasonably distortion free, - Paul t 10:45 PM 1/15/2015, Donald Chester wrote: >----- Original Message ----- > > >>>>From: Paul Baldock > >I'm building a modulator with 2 x 813's in pushpull (strapped as >triodes) driven by a 20W Solid State audio amplifier. I need a driver >transformer to go between the 813 grids and the 20W amp. The 20W amp >can drive about 20V peak to peak. I think I need about 200V peak to >peak for the 813's, so a 10:1 turns ratio ratio would be about right. >So based on that an audio transformer designed to go from 600Ohms >center tapped to 4 or 8 ohms would probably do the job. Have I got >the math right? Does something like this exist? > >Thanks > >Paul >>>>> > >For best results, use the least amount of step-up possible to just barely >get the required peak-to-peak audio voltage, with a little bit of additional >head-room. Ideally, the driver amplifier will go into saturation (flat-top) >at the same instant that the modulator is driven to its maximum capability. >IOW, the driver and modulator stage reach saturation at the same time. I >would design in a little extra margin, so that the driver is capable of >driving the modulator slightly beyond saturation, just to make sure you get >the maximum undistorted audio power out of the modulator before the driver >starts clipping. > >A typical class-B grid impedance varies widely over the audio cycle, from >infinite ohms (on the negative half of the cycle when the tube is not >conducting, down to a minimum of about 500 ohms at the crest of the positive >peak. The grid voltage / grid impedance curve will likely be non-linear. The >total impedance of the whole mid-tapped winding would be something like 4 >times 500 ohms, or 2000 ohms. Using the 8-ohm tap, the impedance ratio would >be 8 ohms to 2000 ohms, or a 1:250 Z ratio. That would be equivalent to a 1 >: 15.8 turns ratio. The 4-ohm tap would require more step-up, 1 : 22.7. > >I doubt that a 600 ohms to 8 ohms transformer would give enough voltage >swing. It may be hard to find an output transformer with a primary impedance >as low as 2000 ohms at that power level, although I'm sure such a thing >exists somewhere. In the real world, I would look for a good quality hi-fi >output transformer rated for at least 20 watts, and preferably 30 watts or >more, with as low a plate-to-plate impedance on the primary as you can >find, but nothing much below 2000 ohms. > >A (backwards wired) transformer with more step-up will deliver more >peak-to-peak voltage to the grid, but the effective internal resistance of >the source voltage will be increased, giving more distortion as the audio >source voltage regulation is degraded. Putting it another way, using too >much step-up, the grids of the tube will cause the audio voltage output from >the transformer to sag. Ideally you might find a transformer with multiple >taps so you could experiment to find the optimum turns ratio, but you'll >have to make do with the best you can find. > >Also, a transformer rated for higher power (and lower primary impedance) >will tend to have lower winding resistance, which would reduce the audio >voltage sag. > >Once you have found what looks like a suitable transformer, try both the >4-ohm and 8-ohm tap and see which one gives the most satisfactory results >with the least distortion. > > >Don k4kyv > > > > > >--- >This email has been checked for viruses by Avast antivirus software. >http://www.avast.com > >______________________________________________________________ >Our Main Website: http://www.amfone.net >AMRadio mailing list >Archives: http://mailman.qth.net/pipermail/amradio/ >List Rules (must read!): http://w5ami.net/amradiofaq.html >List Home: http://mailman.qth.net/mailman/listinfo/amradio >Post: AMRadio at mailman.qth.net >To unsubscribe, send an email to amradio-request at mailman.qth.net with >the word unsubscribe in the message body. > >This list hosted by: http://www.qsl.net >Please help support this email list: http://www.qsl.net/donate.html From rbethman at comcast.net Fri Jan 16 12:27:23 2015 From: rbethman at comcast.net (rbethman) Date: Fri, 16 Jan 2015 12:27:23 -0500 Subject: [AMRadio] AM In-Reply-To: <007e01d03164$170923f0$451b6bd0$@charter.net> References: <007e01d03164$170923f0$451b6bd0$@charter.net> Message-ID: <54B949FB.6060107@comcast.net> On 1/16/2015 3:11 AM, Donald Chester wrote: >>>>> The amateur community has been brainwashed into the almighty Bird > Wattmeter is "the standard". > > Regards, Bob - N0DGN >>>>> > > Just as the AM community has been brainwashed into the p.e.p. nonsense. Case > in point: " The Scratchy Apache will hold 100W carrier and 400W Modulated > output." > > "Modulated output" my arse. The Apache is a 100-watt transmitter. > > > And I might add, I wouldn't have any use for a Bird Wattmeter even if > someone gave me one. There isn't a sprig of coax anywhere in my entire > transmitting antenna system, from the plates of the final to the radiating > element of the antenna. Everything is tied together with link coupling and > balanced open wire line - the real stuff, #8 and #10 copperweld spaced 2 > 1/2 and 2 inches apart respectively. None of that oversize TV ribbon with > the square holes punched in the insulation every few inches. > > > Don k4kyv I never posted with the intent of "starting" any form of a back and forth. However, I would be surprised if the majority of AM Operators use balanced open wire feeds. I can only speak for myself, yet I can say that I have never had the pleasure or displeasure of assembling such. I am one that has had to move on a fairly constant basis, and have not been afforded the ability to use such a network of feeders. I have been "stuck" with coaxial feed lines. That is where my comments were directed. End of my commentary. Regards, Bob - N0DGN From k4kyv at charter.net Fri Jan 16 15:35:43 2015 From: k4kyv at charter.net (Donald Chester) Date: Fri, 16 Jan 2015 14:35:43 -0600 Subject: [AMRadio] AMRadio Digest, Vol 132, Issue 11 In-Reply-To: References: Message-ID: <000c01d031cc$0047f6b0$00d7e410$@charter.net> John, WA0STX, To answer your question, I tried to respond by e-mail, but my message bounced. Others here considering using open wire line might be interested in the same thing, so here it is. Look in your 1965 edition of the ARRL Radio Amateur's Handbook, or an earlier one if you have one around. I'm less sure about the big thick recent editions in the large format; they took a lot of the practical stuff out, making them all but useless as a source of basic homebrewing information, at least for the kind of stuff I like to build. The last new one I bought was about 10 years ago and I thought it was a waste of money. My OWL consists of #8 copperweld spaced 2 1/2 inches apart, and #10 spaced 2" apart. Some of the spreaders are homemade while others are the little EF Johnson 2" ceramic jobs. The impedance calculates to 438 ohms. I used that impedance because of the availability of the 2" spreaders; I had a bunch of them on hand. The 2" spacing is also ideal for feeding up through the interior of the tower, at the geometric centre of the triangle, rather than the usual Hammy Hambone technique of a Rube-Goldberg outrigger to space the line some distance away from the tower. The heavier line, the 140' long run from shack to tower, uses wider spacing to maintain the same Zo with the larger diameter wire, in case I ever have a reason to connect the entire thing together to form one single tuned feed line. I used copperweld wire simply because I had it available; I had acquired several thousand feet of #8 and #10 over the years. If I had to buy new wire, I would have looked for solid #8 hard-drawn copper for the shack-to-tower OWL. Copperweld is too stiff for easily making OWL, but good for antenna wire since it is practically indestructible. The older chap (now SK) who gave me the roll of #8 had used the stuff as guy wire for a couple of 100' towers, and they had been up for over 10 years. The spreaders are attached to the line using short pieces of smaller gauge copper wire, just as described in the older handbooks. The main transmission line wires ride in the grooves at the ends of the spreaders, with the smaller wire threaded through the holes near the ends of the spreaders and wrapped round the main wires to hold them in place. The run up the tower, OTOH, is held in place by spacers made out of plexiglass sheet, one every 10', fixed to a set of rungs on each tower section. Each spacer has two holes drilled in it, 2" apart, with the wires threaded through the holes as they run down the tower. Tension on both the OWLs is maintained using small turnbuckles. I used a come-along for the initial tension on the shack-tower line while I was putting it together. The shack-to-tower line is matched (flat, non-resonant, with no standing waves), while the line from enclosure at the base of the tower up to the doublet operates as a tuned line with standing waves. Since I designed and built the transmitter and antenna feed system myself, it was my decision to designate the tuned circuits at the base of the tower as an integral part of the transmitter; this final stage of the output network is linked back to the earlier stages via the untuned line, while the tuned feed line running up the tower is designated as the antenna transmission line. That configuration tunes more satisfactorily than would one long tuned feed line with an "antenna tuner" in the shack. The network stage at the base of the tower is remotely tuned from the shack, using a reversible DC motor, ganged with a meter rheostat on the same shaft, to indicate the setting of the tuning capacitors. If you have any further questions, please don't hesitate to ask. Don -----Original Message----- I'm back near DC again having abandoned my plans of moving back to the Midwest. So now I need to restring all my antennas and I want to do it right this time. You mentioned not using the commercial (and assumed crappy) open line. Can you tell me of a good place where I might read about the proper construction and measurements to this open line you homebrewed. I need to start at the beginning and study the entire matter. Any assistance you can provide would be greatly appreciated. I hope to be back on the air again soon with my Valiant and my 1965 ARRL handbook homebrew superhet ! --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com From aar7ir at hotmail.com Fri Jan 16 15:53:45 2015 From: aar7ir at hotmail.com (WA0STX) Date: Fri, 16 Jan 2015 15:53:45 -0500 Subject: [AMRadio] AMRadio Digest, Vol 132, Issue 11 In-Reply-To: <000c01d031cc$0047f6b0$00d7e410$@charter.net> References: <000c01d031cc$0047f6b0$00d7e410$@charter.net> Message-ID: Don, This is great, thanks so much for taking the time to share ! I'll keep you up to date with my progress. Regards, John WA?STX/4 -----Original Message----- From: AMRadio [mailto:amradio-bounces at mailman.qth.net] On Behalf Of Donald Chester Sent: Friday, January 16, 2015 3:36 PM To: amradio at mailman.qth.net Subject: Re: [AMRadio] AMRadio Digest, Vol 132, Issue 11 John, WA0STX, To answer your question, I tried to respond by e-mail, but my message bounced. Others here considering using open wire line might be interested in the same thing, so here it is. Look in your 1965 edition of the ARRL Radio Amateur's Handbook, or an earlier one if you have one around. I'm less sure about the big thick recent editions in the large format; they took a lot of the practical stuff out, making them all but useless as a source of basic homebrewing information, at least for the kind of stuff I like to build. The last new one I bought was about 10 years ago and I thought it was a waste of money. My OWL consists of #8 copperweld spaced 2 1/2 inches apart, and #10 spaced 2" apart. Some of the spreaders are homemade while others are the little EF Johnson 2" ceramic jobs. The impedance calculates to 438 ohms. I used that impedance because of the availability of the 2" spreaders; I had a bunch of them on hand. The 2" spacing is also ideal for feeding up through the interior of the tower, at the geometric centre of the triangle, rather than the usual Hammy Hambone technique of a Rube-Goldberg outrigger to space the line some distance away from the tower. The heavier line, the 140' long run from shack to tower, uses wider spacing to maintain the same Zo with the larger diameter wire, in case I ever have a reason to connect the entire thing together to form one single tuned feed line. I used copperweld wire simply because I had it available; I had acquired several thousand feet of #8 and #10 over the years. If I had to buy new wire, I would have looked for solid #8 hard-drawn copper for the shack-to-tower OWL. Copperweld is too stiff for easily making OWL, but good for antenna wire since it is practically indestructible. The older chap (now SK) who gave me the roll of #8 had used the stuff as guy wire for a couple of 100' towers, and they had been up for over 10 years. The spreaders are attached to the line using short pieces of smaller gauge copper wire, just as described in the older handbooks. The main transmission line wires ride in the grooves at the ends of the spreaders, with the smaller wire threaded through the holes near the ends of the spreaders and wrapped round the main wires to hold them in place. The run up the tower, OTOH, is held in place by spacers made out of plexiglass sheet, one every 10', fixed to a set of rungs on each tower section. Each spacer has two holes drilled in it, 2" apart, with the wires threaded through the holes as they run down the tower. Tension on both the OWLs is maintained using small turnbuckles. I used a come-along for the initial tension on the shack-tower line while I was putting it together. The shack-to-tower line is matched (flat, non-resonant, with no standing waves), while the line from enclosure at the base of the tower up to the doublet operates as a tuned line with standing waves. Since I designed and built the transmitter and antenna feed system myself, it was my decision to designate the tuned circuits at the base of the tower as an integral part of the transmitter; this final stage of the output network is linked back to the earlier stages via the untuned line, while the tuned feed line running up the tower is designated as the antenna transmission line. That configuration tunes more satisfactorily than would one long tuned feed line with an "antenna tuner" in the shack. The network stage at the base of the tower is remotely tuned from the shack, using a reversible DC motor, ganged with a meter rheostat on the same shaft, to indicate the setting of the tuning capacitors. If you have any further questions, please don't hesitate to ask. Don -----Original Message----- I'm back near DC again having abandoned my plans of moving back to the Midwest. So now I need to restring all my antennas and I want to do it right this time. You mentioned not using the commercial (and assumed crappy) open line. Can you tell me of a good place where I might read about the proper construction and measurements to this open line you homebrewed. I need to start at the beginning and study the entire matter. Any assistance you can provide would be greatly appreciated. I hope to be back on the air again soon with my Valiant and my 1965 ARRL handbook homebrew superhet ! --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Archives: http://mailman.qth.net/pipermail/amradio/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: AMRadio at mailman.qth.net To unsubscribe, send an email to amradio-request at mailman.qth.net with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html From k4kyv at charter.net Fri Jan 16 17:11:06 2015 From: k4kyv at charter.net (Donald Chester) Date: Fri, 16 Jan 2015 16:11:06 -0600 Subject: [AMRadio] AMRadio Digest, Vol 132, Issue 12 In-Reply-To: References: Message-ID: <000301d031d9$5345c510$f9d14f30$@charter.net> >----- Original Message ----- From: Paul Baldock Thanks for your input. I finished up using two step up transformers with the 8 ohms sides in parallel and the 500 Ohm sides in series to simulate a center tap. So that is effectively 8 Ohms to 2000 Ohms, center tapped. Testing in to a 1K resistive load the output looks reasonably distortion free, >>>> That should work fine, since each modulator tube is active over only half the audio cycle, and each side of the midtapped secondary coil of a real push-pull transformer would be acting as a separate transformer driving a separate tube anyway, while the other half idles with no load. Gates used a somewhat similar configuration in the BC1-J transmitter, except that they had a pair of what were probably 30-watt public address or jukebox amplifiers, and used the 500-ohm output tap on each unit to independently drive each 833A grid, and drove the input to each separate amplifier 180? out of phase with the other one to maintain proper push-pull operation. Your lash-up probably will have less distortion than would a 5K or 10K push-pull output transformer wired backwards. Hope it works well when you actually connect it to the 813s. Actually, the transformer impedance ratio would be rated as 8 ohms to 500 ohms, total primary to 1/2 secondary, even if one single transformer were used. It doesn't really act as a 2K winding, since only half the winding is delivering power at any one time, unlike the case of a class-A amplifier where the entire winding works over the full audio cycle. It took me a long time to figure that one out, years ago. Don --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com From jc at pctechref.com Fri Jan 16 17:34:13 2015 From: jc at pctechref.com (John Coleman) Date: Fri, 16 Jan 2015 16:34:13 -0600 Subject: [AMRadio] AMRadio Digest, Vol 132, Issue 12 In-Reply-To: <000301d031d9$5345c510$f9d14f30$@charter.net> References: <000301d031d9$5345c510$f9d14f30$@charter.net> Message-ID: <005801d031dc$8e2bb6a0$aa8323e0$@com> Since we are on the transmission line stuff. I will add some finding of my own. I have develop a method for measuring very accurately the Peak Rf voltage across a 50 ohm dummy load, but that is another story. I was running a rig that would easily put 300 volts Peak across the dummy load. I tuned it up into a length of 100ft RG8 with the meter and dummy load out in the yard. Making very precise measurement on the plate current dip and the plate supply voltage and the local SWR meter showed no return voltage at the most sensitive setting. I then quickly went out to the dummy load to measure the RF peak voltage before the dummy load boiled over. Made the note and ran back to kill the XMTR. I then connected the dummy load to 60 feet of open wire line which was suspended in the air by strings from the trees and came to a balanced Johnson match box mounted under the eve of the house. Ten feet of coax went to the matchbox from the same SWR bridge. I then place the XMTR with a very low plate voltage and tuned the matchbox for no return voltage. Then flipped the switch on the XMTR to normal HV and checked that there was still no return voltage on the SWR bridge. And that HV and Plate current were same as before. I then quickly went and measured the peak RF voltage at the 50 ohm dummy load and found that it was a few volts higher than with the coax straight. I did this many times at various power levels and it was always the same. The balanced open wire line with the KW Johnson MatchBox delivered a little bit more and when I say a little bit I mean very little more than the straight COAX. The difference was extremely small but I was expecting it to be more with the straight coax 100ft long. So if someone tells you those tuners and balanced line have a loss, it is true, but not as much loss as 100 feet of COAX. BTW this was all at 3.885 MHZ John, WA5BXO From k4kyv at charter.net Fri Jan 16 19:55:31 2015 From: k4kyv at charter.net (Donald Chester) Date: Fri, 16 Jan 2015 18:55:31 -0600 Subject: [AMRadio] AMRadio Digest, Vol 132, Issue 11 In-Reply-To: References: Message-ID: <000601d031f0$4b1f5100$e15df300$@charter.net> ----- Original Message ----- >The ARRL had nothing to do with either one of these rules. The ARRL even fought against the removal of the code requirement. >Pete, wa2cwa On Thu, 15 Jan 2015 06:35:51 -0800 CL in NC via AMRadio writes: >>Yes, the ARRL through the FCC screwed us with the 1500 watt PEP rule that translates to approx. 375 watts carrier out, just like they did by forcing the FCC's hand on the code requirement where the FCC got fed up and removed it all. > Charlie, W4MEC in NC >> And to be fair, the ARRL actively supported the AM community during the power debacle. They submitted comments on our behalf, and then submitted a petition for reconsideration asking to grandfather the existing power standard for AM. But once the FCC announced their final ruling, they showed no further interest in the cause, and further correspondence to headquarters on the subject went unanswered. One person to whom we probably can direct some of the blame is K1MAN, although by that time Johnston and his henchmen at the FCC's Private Radio Bureau undoubtedly had already made up their minds, so that any "proceedings" on the issue were a mere formality. Baxter had filed a lawsuit against the FCC in federal court before the final administrative proceedings had were terminated. I remember Dave Sumner saying that Baxter's ill-conceived and ill-timed legal action had the effect of hardening the FCC's position and that henceforth it would be much more difficult to get them to budge on the issue. At the FCC Forum at Dayton the following spring, during the Q-A session that followed, Johnny Johnston who MC'ed the forum, was asked if the FCC was going to follow through on their stated commitment as written in the original NPRM to "revisit" the power issue in 1990 "if there was any justification to do so". Johnston replied with a sneer, "you took us to court, remember". The questioner then retorted that it was K1MAN who brought the court case, not "us". Johnston responded, "As far as I am concerned it was the amateur radio community. That's an issue that got caught up in circumstances". Then without pausing for a breath he continued with some unrelated drivel without giving anyone else any chance to respond. For the court proceedings, Baxter had typed up a well-researched paper brief, but according to a group of AMers who had made the trek to D.C. and attended in person, acting as his own lawyer in court, he completely blew his case before the judge by getting off track into a diatribe about the Mexican earthquake and how his self-proclaimed "American Amateur Radio Network" had helped save the day, and that a power cut would have severely hampered their efforts. Thing was, his group's "efforts" were carried out entirely on 20m slopbucket, not AM. What did that have to do with the case? After the judge ruled against his petition, saying that the court was "deferring to the expertise" of the FCC, Baxter then filed an appeal to the US Supreme Court, but as expected, they wouldn't hear the case. Don k4kyv --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com From wa1zuf at juno.com Fri Jan 16 20:12:24 2015 From: wa1zuf at juno.com (Steve Belcher) Date: Fri, 16 Jan 2015 20:12:24 -0500 Subject: [AMRadio] AM Message-ID: I am open wire... I'll never look back to co-ass. :)? Sent via the Samsung Galaxy S? III, an AT&T 4G LTE smartphone
-------- Original message --------
From: rbethman
Date:01/16/2015 12:27 PM (GMT-05:00)
To: amradio at mailman.qth.net
Subject: Re: [AMRadio] AM
On 1/16/2015 3:11 AM, Donald Chester wrote: >>>>> The amateur community has been brainwashed into the almighty Bird > Wattmeter is "the standard". > > Regards, Bob - N0DGN >>>>> > > Just as the AM community has been brainwashed into the p.e.p. nonsense. Case > in point: " The Scratchy Apache will hold 100W carrier and 400W Modulated > output." > > "Modulated output" my arse. The Apache is a 100-watt transmitter. > > > And I might add, I wouldn't have any use for a Bird Wattmeter even if > someone gave me one. There isn't a sprig of coax anywhere in my entire > transmitting antenna system, from the plates of the final to the radiating > element of the antenna. Everything is tied together with link coupling and > balanced open wire line - the real stuff, #8 and #10 copperweld spaced 2 > 1/2 and 2 inches apart respectively. None of that oversize TV ribbon with > the square holes punched in the insulation every few inches. > > > Don k4kyv I never posted with the intent of "starting" any form of a back and forth. However, I would be surprised if the majority of AM Operators use balanced open wire feeds. I can only speak for myself, yet I can say that I have never had the pleasure or displeasure of assembling such. I am one that has had to move on a fairly constant basis, and have not been afforded the ability to use such a network of feeders. I have been "stuck" with coaxial feed lines. That is where my comments were directed. End of my commentary. Regards, Bob - N0DGN ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Archives: http://mailman.qth.net/pipermail/amradio/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: AMRadio at mailman.qth.net To unsubscribe, send an email to amradio-request at mailman.qth.net with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html From tobiebw2 at newmexico.com Fri Jan 16 20:54:59 2015 From: tobiebw2 at newmexico.com (Steve Wender) Date: Fri, 16 Jan 2015 19:54:59 -0600 Subject: [AMRadio] Antenna relays Message-ID: <54B9C0F3.5000909@newmexico.com> Hi All, What are your thoughts and experiences with antenna relays to switch an antenna from transmitters to receivers. I have used Dow Key relays with pl259 connectors but I wonder if there are better things that can be made from regular relays in terms of signal attenuation etc. Thanks, Steve KC5WN From ranchorobbo at gmail.com Sat Jan 17 07:04:17 2015 From: ranchorobbo at gmail.com (Rob Atkinson) Date: Sat, 17 Jan 2015 06:04:17 -0600 Subject: [AMRadio] Antenna relays In-Reply-To: <54B9C0F3.5000909@newmexico.com> References: <54B9C0F3.5000909@newmexico.com> Message-ID: It depends on the frequency and type of feedline. You can use open frame relays with widely spaced contacts for open wire line. EFJ made such a relay (they are found in the KW Matchboxes). I use a large 4PDT P&B relay inside an aluminum die cast enclosure for the low bands. It all depends on how much impedance bump you can tolerate. If you use unbalanced coaxial line, preserving the geometry of the line through the switch is probably only important at VHF. Tube rigs don't care even up there I bet. I paralleled 3 poles for RF and used the fourth one to ground the rx line on transmit. It will handle a KW carrier with no problem. What is important is that the relay you employ, is a relay with the RF path consisting of non-ferrrous metals, copper, brass, aluminum, silver. Some steels vibrate with RF at the microscopic level and that produces heat. 73 Rob K5UJ On Fri, Jan 16, 2015 at 7:54 PM, Steve Wender wrote: > Hi All, > > What are your thoughts and experiences with antenna relays to switch an > antenna from transmitters to receivers. I have used Dow Key relays with > pl259 connectors but I wonder if there are better things that can be made > from regular relays in terms of signal attenuation etc. > > Thanks, > > Steve > KC5WN From deswynar at xplornet.ca Sun Jan 18 13:19:26 2015 From: deswynar at xplornet.ca (Eddy Swynar) Date: Sun, 18 Jan 2015 13:19:26 -0500 Subject: [AMRadio] Wireles No. 19 Sets Message-ID: <61AF7E65-B9B8-479B-B3E3-78DAF8E33AB2@xplornet.ca> Hi Guys, No pecuniary interest in this whatsoever, but I think there are more than a few Hams around who are interested in this sorta stuff: http://www.kijiji.ca/v-electronics/owen-sound/two-19-set-mkii-used-for-ham-radio-parts-or-restore/1039980085?enableSearchNavigationFlag=true ~73!~ de Eddy VE3CUI - VE3XZ From wa1qix at piesky.com Mon Jan 19 23:10:53 2015 From: wa1qix at piesky.com (Steve WA1QIX) Date: Mon, 19 Jan 2015 23:10:53 -0500 Subject: [AMRadio] Calling the Lonely Guys! (Get-together on 1/24/2015 in CT) In-Reply-To: <61AF7E65-B9B8-479B-B3E3-78DAF8E33AB2@xplornet.ca> References: <61AF7E65-B9B8-479B-B3E3-78DAF8E33AB2@xplornet.ca> Message-ID: <201501200409.t0K495pv081909@mns1.townsend.ma.us> Calling the Lonely Guys! The Lonely Guys Net meets on Saturday mornings at 8:00 on or about 3875 (give or take QRM, etc.). The purpose of the Net is fellowship; we seek to support each other in our RF loneliness. There is a weekly topic, and we generally get from between 20 to 30 check-ins per week. It is a very fun net and joining is simple. Each member is assigned a lifetime net number. Anyway, The Lonely Guys Net is having a Luncheon and get-together on Saturday January 24th at 12:00 for net members and their spouses at: The Maple Tree Cafe 781 Hopmeadow St Simsbury, CT 06070 Phone number (860) 651-1297 Note that we are encouraging net members to bring their spouses along as well ! We have a function room reserved for this event. Several guest speakers have been engaged, including someone reasonably high up in the ARRL. Off hand, I don't remember who it is, as I did not personally make these arrangements. We are also having custom and very good quality Lonely Guys hats made up for net members. The cost will be approximately $15.00. Please let me know if you want a hat and/or if you are coming (if you have not already told me, Peter W1ZZZ or Jim WA1UQM, that is). Questions? Contact me (Steve WA1QIX), Peter W1ZZZ or Jim WA1UQM. This is always a fun event with plenty of surprises! If you're a member of the Lonely Guys, please let us know if you are coming (if we have not already done so on the air during the net) so we can get an approximate head count. Email me at wa1qix at classeradio.com. I am also good in QRZ. From w5jo at brightok.net Thu Jan 22 12:21:04 2015 From: w5jo at brightok.net (Jim Wilhite) Date: Thu, 22 Jan 2015 11:21:04 -0600 Subject: [AMRadio] Need switch Message-ID: I am looking for a switch that fits a GK 500A, B or C. The one in question is for the coarse loading control. It is a 6 position, 20 amp switch with 5 progressive shorting contacts. Either it or the main bandswitch for the final tank circuit will do. Should you have one I would like to purchase. The original switch was made by Centralab but there may be alternatives out there. The only restrictions are mounting is by a 3/8 shaft and nut and the switch fits under a 3 inch chassis. Any leads would be appreciated. From hallicrafterssr2000 at k9axn.com Thu Jan 22 14:07:23 2015 From: hallicrafterssr2000 at k9axn.com (Jim Liles) Date: Thu, 22 Jan 2015 13:07:23 -0600 Subject: [AMRadio] Need switch In-Reply-To: References: Message-ID: <9041BC58C79B4ED4B966598D6C87C687@LILESJLAPTOP> Hi Jim, Send a close up of the switch and the dimensions. If it?s the 1 7/8? Centralabs might be able to help. You indicate it is a 20 amp switch. The single contact 1 7/8? Centralabs switches were 9 amp, and with a contact on both sides, 18 amps. The 1 7/8? double contact switch was used in the SR-2000 NCL-2000 and a plethora of other amps. Both of those amps had a maximum of 15 amps circulating in the tank in high power mode and the switch easily handled the current. Tests using SSB indicated that a single contact could carry the load in high power mode but would be severely stressed in AM mode. Take a quick look at http://www.k9axn.com/_mgxroot/page_10872.html. Does this look like the switch that you need albeit a different configuration? Kindest regards Jim K9AXN -----Original Message----- From: Jim Wilhite Sent: Thursday, January 22, 2015 11:21 AM To: AM Radio List Subject: [AMRadio] Need switch I am looking for a switch that fits a GK 500A, B or C. The one in question is for the coarse loading control. It is a 6 position, 20 amp switch with 5 progressive shorting contacts. Either it or the main bandswitch for the final tank circuit will do. Should you have one I would like to purchase. The original switch was made by Centralab but there may be alternatives out there. The only restrictions are mounting is by a 3/8 shaft and nut and the switch fits under a 3 inch chassis. Any leads would be appreciated. ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Archives: http://mailman.qth.net/pipermail/amradio/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: AMRadio at mailman.qth.net To unsubscribe, send an email to amradio-request at mailman.qth.net with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html From wa1qix at piesky.com Thu Jan 22 21:54:07 2015 From: wa1qix at piesky.com (Steve WA1QIX) Date: Thu, 22 Jan 2015 21:54:07 -0500 Subject: [AMRadio] ***POSTPONED*** The Lonely Guys! (Get-together was 1/24/2015 in CT) Message-ID: <201501230254.t0N2sRZA074046@mx1.piesky.com> This event has been postponed due to the impending storm coming in this weekend! A new event date will be announced shortly. -------------------------- Original post ------------------------------- Calling the Lonely Guys! The Lonely Guys Net meets on Saturday mornings at 8:00 on or about 3875 (give or take QRM, etc.). The purpose of the Net is fellowship; we seek to support each other in our RF loneliness. There is a weekly topic, and we generally get from between 20 to 30 check-ins per week. It is a very fun net and joining is simple. Each member is assigned a lifetime net number. Anyway, The Lonely Guys Net is having a Luncheon and get-together on Saturday January 24th at 12:00 for net members and their spouses at: The Maple Tree Cafe 781 Hopmeadow St Simsbury, CT 06070 Phone number (860) 651-1297 Note that we are encouraging net members to bring their spouses along as well ! We have a function room reserved for this event. Several guest speakers have been engaged, including someone reasonably high up in the ARRL. Off hand, I don't remember who it is, as I did not personally make these arrangements. We are also having custom and very good quality Lonely Guys hats made up for net members. The cost will be approximately $15.00. Please let me know if you want a hat and/or if you are coming (if you have not already told me, Peter W1ZZZ or Jim WA1UQM, that is). Questions? Contact me (Steve WA1QIX), Peter W1ZZZ or Jim WA1UQM. This is always a fun event with plenty of surprises! If you're a member of the Lonely Guys, please let us know if you are coming (if we have not already done so on the air during the net) so we can get an approximate head count. Email me at wa1qix at classeradio.com. I am also good in QRZ. From knjhanlon at msn.com Fri Jan 23 14:28:02 2015 From: knjhanlon at msn.com (JAMES HANLON) Date: Fri, 23 Jan 2015 12:28:02 -0700 Subject: [AMRadio] Antenna Relays Message-ID: Steve, I like to operate QSK (break-in) CW and I use a relay to switch the 50 ohm antenna line coming from my transmatch and going to either my receiver or my transmitter. I use a Western Electric mercury wetted relay, they type housed in an octal-based tube casing about the size of a metal 6V6. You can find suitable relays on the Surplus Sales of Nebraska web site at https:// blu184.mail.live.com/?pages=compose . The 276G relay has one SPDT contact and a 700 ohm coil that they rate for 12 to 24 vdc. It sells for $10. Actually the contacts are a little more complicated than just the normal SPDT switch. Each stationary contact, on both the normally closed side and the normally open side, has two electrodes mechanically and electrically separated from one another. The "swinger" contact has a bar which makes contact with both of the stationary contacts and shorts them together. They were made this way, I think, to perform a logic function in the old, electromechanical telephone exchanges. But you can just wire the two normally-open contacts together and the two normally-closed contacts together and treat them like a standard SPDT relay. The DC rating for the 276 relay contacts is 5 amps maximum. I have a time-sequenced keying circuit so that I don't turn on the transmitter until after the antenna relay has completed its switching cycle - I don't "hot switch" my antenna relay. Used in this service, my 276 relay holds the output of my Heathkit SB-200 amplifier, about 600 watts, into a nominal 50 ohm load. That works out to about 3.46 amps of RF current. 5 amps would work out to 1250 watts through the relay. The reasons why I use a mercury-wetted relay are as follows. They are "fast" as relays go, they operate and release in less than 1 millisecond. They have very low contact resistance, under 20 milliohms. They have absolutely no contact "bounce" like normal, dry contact relays have. Once the contacts close, they stay closed, once they open they stay open. Now that I think about it, the 276 type relay actually has a short period of time during the operating cycle when the NO contacts, the swinger, and the NC contacts are all bridged together. But this gives me no problem since I don't turn my transmitter on until after the antenna relay switching cycle is completed and I turn the transmitter off before I release the antenna relay. One caution, the mercury wetted relays must be operated reasonably close to vertical, upright, with the octal base down. If you turn them "upside down," the liquid mercury inside can flow down onto the contacts and the swinger and short them out. I have no noticeable problem with an "impedance bump" with this antenna relay through 10 meters. I operate it with both tube-type transmitters and with a Ten Tec Triton IV transceiver. If you'd be interested in further information on my QSK keyer, I can supply a copy of an article that I wrote about it for Electric Radio Magazine, October 1996, page 20. My keyer switches the antenna relay and generates separate, nested keying closures for the oscillator and amplifier stages of my transmitters. So the keying sequence when I press and release my key goes: 1-Antenna relay transfer from receiver to transmitter and receiver cutback, 2- Oscillator key closure, 3-Amplifier key closure, 4-Amplifier key opening, 5-Oscillator key opening, 6-Antenna relay transfer from transmitter to receiver and receiver recovery. This all happens fast enough so that I am able to listen to what's going on between dots and dashes to well over 30 wpm. I'm not enough of a CW speed demon to ever have pushed it to the point where it doesn't recover between characters. Hope this is interesting, Jim Hanlon, W8KGI From kenw8ek at gmail.com Sat Jan 24 10:44:24 2015 From: kenw8ek at gmail.com (Ken Simpson, W8EK) Date: Sat, 24 Jan 2015 10:44:24 -0500 Subject: [AMRadio] HF Antenna Tuner and HF related antenna items FS Message-ID: <54C3BDD8.4020109@gmail.com> HF Antenna Tuner and HF Antenna related items For Sale: Murch UT-2000, 2 KW HF Antenna Tuner: The Murch tuner followed the "Ultimate Transmatch" design that appeared for many, many years in the ARRL Handbook. It was considered to be the absolute top of the line HF tuner. It is rated at 2000 watts, 80 thru 10 meters. Once one looks at the inside, it is easy to see why. The roller inductor is HUGE. So is the spacing on the capacitors. This is a very rugged tuner. The front panel says this is a UT-2000. The plain UT-2000 was primarily sold without a meter. This one has a meter with switch for "Off-Fwd-Ref". I think it was available with a meter as an option. The case on Murch tuners originally had a really sick green color. Like most, this one has been repainted and is now a black hammertone that is in excellent shape. This one works fine, and looks exceptionally nice. Paper work for the A and B models is included for $150. CDE Rotor Control Box for 8 wire rotors: This CDE Rotor control box will control any of the CDE/Telex/HyGain 8 wire rotors. This is labeled for use with the Tailtwister, but can be used with Ham M, Ham II, Ham II, or Ham IV, and others as well. This one is in the black case, and is a CDE as opposed to the Telex or HyGain. Most people consider the CDE higher quality. This one has the LEDs showing direction of rotation and brake release, in addition to the North centered meter. It has a female 8 pin Jones connector on it. This one works fine and looks really great. Paper work is included for $110. Coaxial Antenna Switches: All work fine, look fine, and use SO-239 connectors. Waters (B & W) Model 376 Protax Coax Switch: This five position switch permits all five antennas to be shorted to ground. It does not short the input connector to ground. This is the Waters "Protax" series, which grounds all unused antennas (or all antennas if in the "ground" position. It accepts PL-259 connectors, with the coax going out like the spokes of a wheel. There is also a mounting bracket if one would want to wall mount it. This one works fine and looks extremely nice. Paperwork is included for $40. Two position "Strip Line" Coax Switch: The MFJ 1702 C switch utilizes metal cavity construction for max efficiency and high isolation. This two position coax switch has a new center ground protection! Better than 60 dB isolation at 300 MHz and better than 50 dB at 450MHz. 50 Ohm. The unused terminal is automatically grounded for static and RF protection. It has less than 0.2 dB insertion loss and SWR below 1.2:1. Heavy cavity type construction and SO-239 connectors. Mounting holes. It looks very close to new. With paper work for $25. SCP Comm Switch SC-40-AS Coax Switch Three position antenna switch in rectangular box. Connectors on the back. In original box. May be new. $22 Wattmeter / SWR Bridges: All have SO-239 connectors and work fine. Vanco SWR-2 SWR Bridge / Wattmeter It covers from 1.7 to 150 MHz. It has a single meter, and is actually a 10 W and 100 W full scale watt meter as well as the "normal" SWR meter. It is still in its original box, with original paper work, and appears to be new. $25. Lafayette 99-25835 SWR Bridge This HF single meter SWR Bridge also functions as a field strength meter. This one is also in its original box, with original paper work and appears to be new. $20 Radio Shack 21-524 SWR and Power Meter This HF meter measures both average and PEP power in 20/200/2000 watt ranges as well as functioning as a regular SWR meter. Looks close to new. With paperwork for $25. High Sierra HS-1800 DX/B "Screwdriver" HF Mobile Antenna This HF mobile antenna package includes the HS-1800DX/B antenna, the HS-201C/SS Stainless Steel powder coated mounting bracket, the HS-110A/PC powder coated stainless steel whip, the MM-SSQD powder coated stainless steel quick disconnect, and 60 feet of control cable and coax in the same cable, plus radial package. This is all completely new, unused. A silent key purchased it just before his death, and never unpacked it. It is still sealed in the plastic bags. It cost him $570. Buy this package complete with original manual for only $400. Quick Disconnects, Resonator Spring, Roof Rack Mount Quick Disconnects Hustler QD-1, stainless steel, still sealed in package. $18 Lakeview set of four top portions, and one lower portion, often used with Hamsticks. Like new. $24 Hustler RSS-2, Stainless steel resonator spring Appears to be unused. No blemishes. $10 Astatic "Mirror Mount" or "Roof Rack Mount" Mounts to mirror or roof rack, and takes a PL-259 on one side, and has a 3/8 inch 24 post for the mobile whip on the other. Used for either HF or VHF/UHF antennas. New, still sealed in the package. $12 As above, unused, but out of package. $10 Hustler "Double Talk" Phasing Harness: Back in the 1970's, Hustler sold a harness of coaxial cable that they called a "Double Talk Harness". It was used to connect to two mobile ball mounts, each of which would have an antenna for the same band. In theory, they would be phased such that there was about 3 db gain, but the reality is that they really shined by reducing QSB, in effect acting as a sort of diversity system. This phasing harness looks fine and works fine. $17 Other Hustler HF mobile items: Hustler RSS-2, Stainless steel resonator spring Appears to be unused. No blemishes. $10 Hustler QD-1 Quick Disconnect, new, still sealed in package. $18 Coaxial Cable with "N" Connectors: This cable has a male "N" connector on each end. It is about 60 feet long. The coax is labeled 50-2 V. This piece is in extremely good condition, with heat shrink around the connectors for strain relief. $35 Coax connectors and adapters: Prices are per connector. Several of each are available. Most are unused. SPECIAL: Buy 5 and take 10% off. Buy 10 or more and take 20% off. UG-175 reducing adapters for PL-259 connectors to use with RG-58 $.50 UG-176 reducing adapters for PL-259 connectors to use with RG-8 X or RG-59. Amphenol, still sealed in the package $1 Amphenol crimp type PL-259, sealed in package $3 UHF double female "Barrel connector" $3 UHF "Bulkhead Connector" with mounting hardware Double female, about 2 inches long $6 UHF "T" connector with two female (SO-239) and one male (PL-259) connection $5 BNC HT to PL-259 adapter.(BNC male to UHF female) $5 BNC male for coax cables standard type $2 crimp on type $3 Chassis mount BNC female square mount (uses 4 screws) $3 Amphenol screw in type, sealed in package $4 BNC "T", two female and one male $3 Turnbuckles: I have two sets of turnbuckles. One is a set of three and are larger. The other is a set of five. All of them appear to be new, unused. The set of three has the turnbuckle itself about 6 1/2 inches long, with each of the bolts having 3+ inches of thread, plus the 1+ inch diameter eye. This set is $30. The second set consists of five turnbuckles, and is marked "5" on it. Does this mean it is considered to be a 5 inch turnbuckle? The actual body of it is 3 1/2 inches long, with 2 inches of thread on each of the eye bolts, plus the 1 inch diameter eye. This set is $25. Buy both sets for $50. I also have many other accessories available such as many different types of microphones, HTs, VHF and UHF rigs, HF and VHF/UHF antennas, etc. Just too many to list here. Please e-mail your requests. Prices do not include shipping from Florida. Thanks. 73, Ken, W8EK Ken Simpson E-mail to W8EK at FLHam.net or W8EK at arrl.net Voice Phone (352) 732-8400 From solarelectricjohn at gmail.com Thu Jan 29 07:57:32 2015 From: solarelectricjohn at gmail.com (john nelson) Date: Thu, 29 Jan 2015 06:57:32 -0600 Subject: [AMRadio] Amplifier Message-ID: Good Morning All, I am looking for an home brew amplifier and power supply carrier around 100 watts will be using a viking ranger to excite it. Can pickup 125 miles from Minneapolis. Don't care if not working as long as iron is good. Cash or pay pal. 73 John W0XAZ

This page last updated 22 Oct 2017.