[AMRadio] More Viking 2 news

Brett Gazdzinski Brett.Gazdzinski at verizon.net
Sat Feb 23 10:23:54 EST 2008

I think I can give you a bunch of 807's, I don't and would not use
them anymore, I go with KT88's or KT 90 tubes as modulators.

So, I likely have a crap load of 807's (and 1625's).

Send me your mailing address and I will get what I have out
to you.

You should check the screen and bias voltages at the tube sockets to be
sure they are ok.
Resistors in most applications can be off 20% without causing any problems.


----- Original Message ----- 
From: "Ellen Rugowski" <ellenjoanne2003 at sbcglobal.net>
To: <amradio at mailman.qth.net>
Sent: Friday, February 22, 2008 11:42 PM
Subject: [AMRadio] More Viking 2 news

> Hi Everybody,
> Work's been kind of nuts lately, and I've been pretty burned out.  So, 
> I've
> only been able to work on my Viking II sporadically.  Last Sunday night, I
> finally got around to wiring up my D-104 with the mic connecter Ed, VA3ES
> sent me, for use with my Viking II.  With the mic finally wired up, I was
> able to determine that yes, my Viking 2 is wired up for PTT (the PTT in 
> mine
> works fine). I also was getting OK modulation of of my Viking.  BUT, after
> no more than about 5 seconds of mic keydown, the modulator current would
> surge, and start to run away.  Well, due to the fiasco the CQ 160m Contest
> is turning out to be for me, I decided to work on my Viking 2's modulator
> issue.
> Well, it looks like I found my problem in spades. After only about 2 or 3
> seconds of mic keydown, in spite of the fact that I had the mic gain/audio
> level at zero, the modulator current surged again.  I unkeyed the mic, let
> things settle down, and keyed up the mic again, watching the 807s.  Sure
> enough, the modulator current surged again, and when it was happening, 
> what
> did I see? - a nice BIG arc over between the plate and the grids on one of
> the 807s!  I shut things down, pulled the 807 out that arced, fired up the
> my Viking 2 again, and keyed the mic, with only the non-arcing 807
> installed.  Nothing happened, other than the fact that the modulator 
> current
> stayed
> steady at a pretty low level (due to there only being one 807 installed).
> So, it looks like I need to buy another 807. And maybe, it might
> be wise for me to get two of them, and save the one remaining good one 
> have
> at the present, for a spare. BTW, the resistor on the plate cap for the 
> bad
> 807 is supposed to read 22 ohms. Assuming that's it's your typical +/-10%
> resistor (personally I prefer +/- 5% or better), it shouldn't read more 
> than
> say 25 ohms.  The cap resistor on the bad 807 read 28 ohms.  Well, there
> isn't much more I can do with the Viking 2, until I get the new 807s.  I
> don't feel like pulling off the mic connector I installed for the Viking 2
> (wiring up mic connectors is a pain), and I haven't gotten the mating
> connector yet, that I need to wire up an adapter cable, so I'm out of luck
> with using the Scout for tomorrow's Midwest Classic net.  I'll only be 
> able
> to listen to Rob, run the net.  Well, I think I'm going to call it a 
> night,
> I'm falling asleep.
> 73,
> Ellen - AF9J
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