10-16-2011, 11:19 PM
Pepperoni Wrote:Thanks Arran but the wax dipped mica you mention is actually two individual 370pfd caps and they read well within tolerance. Micas I usually don't replace unless they're way out of tolerance or bad or "Micamolds".
B+ is connected to the CT of the output transformer but the other two primary legs go directly to each plate of each 41 output tube. They're in push-pull configuration. This can be verified by looking at the schematic. My problem doesn't appear to be in the audio circuit but in the front end of the set. The RF section. I've already highlited two schematics verifying all of my connections. I just finished verifying all the bandswitch connections. So far I've found nothing out of place. Tomorrow I'm going to remove the pushbutton assy. and take another look at the underside of that. I'm still pretty baffled. I can't find the problem.
Pepper
How did you test the micas? Did you test them with an ESR meter or a resistance-capacitance bridge where you can put some high voltage across them? When you have replaced everything else and everything seems to be where it should be, failing micas caps is a possibility just due to process of elimination.
Regards
Arran