[Drake] TR-4CW Neutralization

Sun, 20 Jul 2003 15:38:27 -0500

Joe, you could have a ground problem within the unit.  I had some similar
flaky problems some time back with my T-4XB.  Not exactly the same symptoms
but similar.  I never found a hard fast cause of the problem but after
loosening and re-tightening the tube sockets - each is held down with a pair
of screws - and re-doing a number of solder connections such as bypass cap
leads to ground (generally all on the tube sockets) the problems went away.
Oh yes, I used de-Oxit on all metal to metal connections to cut any
oxidation which might be increasing resistance.

This may or may not be related to the neutralizing problem but it might for
the other problems.  Worth a try.

Dan W. Dooley WB5TKA
   email: [email protected]
   http://www.dooleystreasurechest.com

----- Original Message -----
From: "k7mks" <[email protected]>
To: <[email protected]>
Sent: Saturday, July 19, 2003 5:34 PM
Subject: [Drake] TR-4CW Neutralization

Time to call in the experts!  I've tried various combinations of Sylvania
6JB6's, new and used, and 12BY7A's etc and yet final neutralization escapes
me.  20 and 15 are extremely touchy when tuning.  In addition the S-meter
does not wish to stay at zero even after swapping 6BZ6's around.  S-meter
pegs full full scale when the RFG is full CCW; Drake says meter should be
around 50 over 9 or so.  Last but not least - when transmitting the S meter
rests about S-9 or so with no mic audio rather than at 0.

Suspect AGC problems which should not effect neutralization.  Just thought
I'd toss out all the problems at once.  Comments greatfully accepted.

73 Joe k7mks