Fw: [Collins] Low Grid Drive - KWM-2

[AI2Q]

My suggestion would be to go through the alignment procedure. It's a great 
way to localize any problems. Alsom check your filament voltage supply. Low 
filament voltage can cause this kind of problem in a KWM-2.

Vy 73, AI2Q, Alex in Maine
http://users.adelphia.net/~alexmm/ai2q.htm

----- Original Message ----- 
From: Dr.Gerald Johnson
To: franklin6209 at chartermi.net
Cc: collins at mailman.qth.net
Sent: Wednesday, February 16, 2005 10:56 AM
Subject: Re: [Collins] Low Grid Drive - KWM-2


Last time this came up, it proved to be a weak RF driver tube. It could be 
lots of
things though including a weak crystal oscillator tube (that doubles in the 
plate
for 20, 15, and 10 meters), or weak tubes from the last mixer to the RF 
driver
tubes. Could be a band switch contact problem, a coil shield problem, a RF
driver or PA neutralization problem (including the RF feedback), could be 
several
bad trimmers in the RF section not necessarily the same stage for each band,
could be a broken PA neutralization capacitor. Check the tubes first. When 
you
do replace the RF driver tube be sure to neutralize it.

I can be anything in the linear transmit chain that is band switched from 
crystal
oscillator on. Or a combination of things. Check the tubes first.

73, Jerry, K0CQ, Technical Advisor to the CRA

-- 
Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
Reproduction by permission only.