12-07-2017, 08:37 PM
Mike,
I have read that mica caps rarely go bad. Do you test them? If so, do they need to be disconnected or is there another check (open or short) to verify? I have not checked the micas in mine.
I checked the components that you suggested and "poked around" the 2nd audio tube. I didn't find anything. I have a hunch that the overall low volume output and the treble control acting as a reverse volume control are related. Is there anything under those IF expander cans worthy of checking? It doesn't appear to be a simple job to open them up. I have ohmed the coils that had connections that I could get to.
I plan to spend more quality time with my 690 tomorrow night. More suggestions are always wecome!
I have read that mica caps rarely go bad. Do you test them? If so, do they need to be disconnected or is there another check (open or short) to verify? I have not checked the micas in mine.
I checked the components that you suggested and "poked around" the 2nd audio tube. I didn't find anything. I have a hunch that the overall low volume output and the treble control acting as a reverse volume control are related. Is there anything under those IF expander cans worthy of checking? It doesn't appear to be a simple job to open them up. I have ohmed the coils that had connections that I could get to.
I plan to spend more quality time with my 690 tomorrow night. More suggestions are always wecome!
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