The voltage at the top of C406 (feeding T401)? is 2.5v, exactly as expected.
I've checked voltage levels around pins 3, 4, 5 of IC402?and are all at 2.5v, also as expected. I can't see any rf signals aournd IC402 with my 'scope only having 10mV sensitivity (even with the the signal generator output turned up). What other probing would you suggest?
I did wonder whether there was an issue with Q508 or surrounding circuitry, but that would surely show up with the Audio filter sweeps?
Cheers,
Dave
M0JTS
