I wanted to wake up my DCC170 from its Sleeping Beauty slumber after 20 years.
As expected, the electrolytic capacitors had gone low-impedance and the belt had disintegrated.
On top of that, Q816 was only delivering 2.2V instead of 3.4V, so I replaced that as well.
The unit now powers on, but there’s no digital playback. And on analog I get a 1 kHz tone that overlays the analog output. The analog signal is played back, but it’s of course overlaid by the 1 kHz tone.
Has anyone here had this issue and maybe knows how to fix it?
A beep that never stops sounds like a defect in the circuit that generates the (normally short) beeps for the earphones. I don’t remember exactly if the beep oscillator is a discrete circuit or if it’s generated by the microcontroller. Either way, as a workaround, if my hypothesis is correct, plugging the output cable into the line output on the back instead of the earphones output on the left, should be a good temporary workaround.
