[AMRadio] WTB SB-220


Brett gazdzinski Brett.gazdzinski at mci.com
Tue Sep 28 08:14:24 EDT 2004


I know about the DB thing, but people running a bit of power always
seem much stronger than the guys running 25 or 50 watts.

I cant say why, but in a qso with a bunch of people, the guys
running 200 to 300 watts are always much stronger on the meter, and
sounding,
than the 50 watt guys.

For some reason, the biggest jump seems to be between about 25 watts
and 100 watts.
I don't think you HEAR as much change between say 300 and 500 watts,
or even 300 and 600 watts, but go between 25 and 100 watts and it seems very
noticeable at the other end.

Maybe the losses in the antenna circuit are a much bigger percentage
of the power out when running 25 or 50 watts?
 
You can see the difference in signal strength when someone turns up the
power,
and it seems to track with the DB rule, but there still seems to be
some threshold effect in most cases.
With 25 watts, its hard to get clearly above the noise floor in many
cases, while 100 watts and up does it easy in clear band conditions.

Most times, on clear conditions on 40 meters, the guy running the
rice box at 25 watts is just above the noise floor at about 1 s unit.
He may run between s1 and s3.
The guy running 100 watts will run s6 to s9 or higher, and be
arm chair copy. That FIRST 3 to 6 db boost seems to be the most critical. 

And I have NEVER heard someone running 25 watts and a REALLY good antenna
out strapping a 500 watt rig into a regular antenna.


And, although its easy to run an amp and boost power a little, it
seems crazy to run a pair of heavy tubes and get 300 watts out,
when a pair of 813 tubes plate modulated will do 700 watts
of carrier easy, and well over 2000 watts pep!

A pair of 812a's will give 300 watts carrier without trouble!


Brett
N2DTS
  



-----Original Message-----
From: amradio-bounces at mailman.qth.net
[mailto:amradio-bounces at mailman.qth.net] On Behalf Of RJ Mattson
Sent: Monday, September 27, 2004 7:07 PM
To: Discussion of AM Radio
Subject: Re: [AMRadio] WTB SB-220


Again, It would be an S1 signal above a s9/30db level noise -  a barely
perceivable difference. You would have to go from 100 to ~ 6,400 watts to
get an S3 signal above that noise level.  bob...w2ami
www.qrz.com/callsign/w2ami


----- Original Message ----- 
From: "George Pritchard" <gpritchard at comtechpst.com>
To: "'Discussion of AM Radio'" <amradio at mailman.qth.net>
Sent: Monday, September 27, 2004 9:38 AM
Subject: RE: [AMRadio] WTB SB-220


> When the interference is also at 30 over S9(even if it's static 
> crashes) a 36 dB over signal using the 400 watts helps. First put up 
> the best ant... Then crank-it with juice!!! George AB2KC
> 1KW 4X1 lives
>
> -----Original Message-----
> From: amradio-bounces at mailman.qth.net 
> [mailto:amradio-bounces at mailman.qth.net] On Behalf Of RJ Mattson
> Sent: Monday, September 27, 2004 9:27 AM
> To: Discussion of AM Radio
> Subject: Re: [AMRadio] WTB SB-220
>
>
> No matter what the spin, 100 to 400 watts is only 1 s-unit and barely 
> perceptible at the receiver. A 30db/s9 signal is from a good antenna 
> not from 100 or 400 watts.
> bob...w2ami
> www.qrz.com/callsign/w2ami
>
>
> ----- Original Message -----
> From: "Jim Candela" <jcandela at prodigy.net>
> To: <amradio at mailman.qth.net>
> Sent: Sunday, September 26, 2004 10:47 PM
> Subject: Re: [AMRadio] WTB SB-220
> >
> > Hmmm, the boys on 3878 are running 1500 watts pep plus
> > on USB, and there is a 100 watt AM'er calling CQ on
> > 3880. How much of an antenna would the AM'er need to overcome the 
> > S/N ratio? I think Astabula Bill, W8VYZ says it all:
> >
> > http://www.amwindow.org/audio/mov/w8vyz.mov
> >
> > Ever hear Bill running 100 watts? When Bill and Less
> > K6HQI (sk) were regulars on 14286 they had to run
> > heavy iron to hold the frequency. A 100 watt rig was
> > seldom heard whereas a 500 watt rig (that 6db again)
> > was often armchair copy, and sometimes often drive the
> > QRM away.
> >
> > Regards,
> > Jim
> >
> > RJ Mattson <rjmattson at hvi.net> wrote:
> > If you can't get out consistantly with a Viking II,
> > you need an antenna -
> > not an amp.
> > bob...w2ami
> > www.qrz.com/callsign/w2ami
>
>
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