Tim Wescott wrote:


Yes, that's the arrangement -- I've checked the two lower bands ("D" and
"C") and they both have the problem. The other two don't, which is odd --
you'd expect the problems to be worse at the high-frequency end.


Hmmm...shorted turns comes to mind since those coils would have the most
turns. Whithout doing any major surgery could you try to add a few
turns as an experiment to see what the result might be?
Another guess might be moisture having impregnated the coil forms.
Often a good DVM can read a leakage resistance right across the cardboard.
Do you have the correct 6K8 in place (glass vs metal)

-BM