Hello! I have a Technics RS-DC8 with buzzing analog playback.
After a number of problems were fixed and the dreaded SMD elcaps replaced, it still does the same symptom: buzzing with 40-50 Hz (slowly changing frequency, some sound comes from the left side, but almost nothing from the right.
What is done:
-Cleaning of mechanism thoroughly (gear is to be replaced afterall)
-Measuring supply voltages and capacitors in supply and around the head amplifier
-Removed old SMD elcaps and cleaned their residual (see the photo)
It looks like the source is the head amplifier AN7631FHPV. This IC is also gets quickly very warm, or let’s say hot.
Could one of you having such unit confirm this IC gets hot? I’m not yet suspecting the head as a reason behind the sound (the signal is distortion-free, bias voltage present) but is there a chance that this is a head problem? I will measure the analogue read channels, but touching the head will be after every other parts investigated and ruled out.
Digital playback/rec not tried yet (i will drill a tape for this purpose, but until analogue is bad, there is no meaning)