[R-390] Gain drift

[Jacques Fortin]

Dave, speaking about the "funky solder joints" in T502...
Does someone previously removed the internal damping resistors within ?
Meaning R553 and R554 that can be seen in the schematic ?
Both are 47k ohms, 5%, 1/2W.
R511 and R512 in T501 are the same (and should be present also !).

Removal of those resistors was a "modification" recommended by some people
30 years ago !
But the end effect was - in some cases- self-oscillation of the IF stages.
Like having a regenerative receiver within the IF strip...
No wonder then if the gain is very high at turn-on and the global operation
unstable.

Have a check !

73, Jacques, VE2JFE