[Drake] Drake 2B AVC

[windy10605 at juno.com]

Thanks to all who have responded to the above. This is where I'm at:

As Garey and Byron mentioned, the AVC circuit on this receiver is VERY
high impedance and any efforts to measure voltages at the AVC terminal
must be done with a high Z meter. Just as an indication, the
"sensitivity" pot on the back must be set to -1.35V to -1.5V with the RF
gain 
all the way up. When I use a calibrated Fluke which has a 1000Meg input
impedance on the 2V scale and set -1.35V another calibrated instrument
with a 10Meg input measures -1.22V (which is not too bad ....but my
little calibrated DVM which I was using, measures only -0.64V. That means
it has a very low input impedance ....lower than I thought, anyway. This
level sets the upper level of the AVC bias for the RF Gain control, and
it goes all the way to -9V at the other end.

Going to a 6EA8 from the 6U8 improved the signal level about one S-unit.
Changing to a new 6BA6 IF tube (also used for the S-meter) causes it to
kick somewhat higher (2-3 S-units) indicating a higher Gm which the new
tube does have.

The other modification I'm considering is the 6BN7 to 12AX7 audio change
to allow more volume and replace the two diodes with solid state
1N914 diodes. 

73 Kees K5BCQ