A better product name than Philips-CD555 would be Philips-SMFH. SMFH as abbreviation of SoundMachine From Hell. The think drove me crazy the whole day. Whilst I was playing for hours yesterday, today morning it failed. I have to admit that after some hours there machine made a silent but hearable buzz which was not in the audio line and the heatsink at the rear side were getting hot.
First the cassette was not working anymore. It looked like the tape mechanics drain too much current since the relays were not switching and the LED of the tape sensor was going off.
So I had to disassembly everything again and started to search for the reason. I finally figured out that one cable again got loose, it was the ground pin of the tape mechanism. After solving this issues and a quick test I reassembled everything just to figure out that the CD-Player was not working anymore. The LCD stays empty, so I disassembled everything again – getting much faster on this procedure.
No idea how it is possible but than the 12V power for the uProc-Panel failed because the undocumented fusable resistor 3489 got broken. Fine, I replaced this little bastard.
Still not working. Might be another problem with the power supply board was my next idea. As a result, the +5V of the CD-Player were missing. It took me some time to figure out that the fusable resistor 3483 was broken. After I replaced it the CD-Player was blinking “–” but the disc was not spinning. Well, I put the SoundMachine on the side since I needed direct access to the bottom of the power supply panel for measurements. Ok, to keep the long story short – It is a really bad idea to put the machine on the side since the CD-Player is then not working anymore! Just took me an hour to figure it out.
As a conclusion, I should do some research about a replacement for the one-time fuses. They cost too much time and energy.
Finally, before reassembling I checked all the functions and everything was working. The long term test can be redone…