[AMRadio] More Viking 2 news

Ellen Rugowski ellenjoanne2003 at sbcglobal.net
Fri Feb 22 23:42:59 EST 2008

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

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
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.

Ellen - AF9J

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