I have this pre amp / tuner STK808 but FM stereo will not work. Tried VCO and IF adjustment using service manual but no change. Could be a lot of things but have not tried cleaning switch yet.
Any advice appreciated
Any advice appreciated
OK changed caps in power supply section as did this with a 90's Technics Tuner and sorted everything.
Improved sound quality on preamp section after power supply cap change but still no FM stereo. Adjusted T101 to 0v (close as possible) and VCO adjustment according to service manual but no change. Changed some caps near VCO while I had the PCB out as I had the correct ones lying around. PCB a pain to get out as it has no rear access panel.
Quartz lock is fine and mono sound quality is excellent.
Any ideas anyone? I do not have a scope or signal generator.
Improved sound quality on preamp section after power supply cap change but still no FM stereo. Adjusted T101 to 0v (close as possible) and VCO adjustment according to service manual but no change. Changed some caps near VCO while I had the PCB out as I had the correct ones lying around. PCB a pain to get out as it has no rear access panel.
Quartz lock is fine and mono sound quality is excellent.
Any ideas anyone? I do not have a scope or signal generator.
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Unfortunately the tools required to align the IF and stereo decoder include an FM signal generator, without a 100.1MHZ modulated at 400HZ generator it is all guess work.
Check the stereo/mono switch!
Check the stereo/mono switch!
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