Hello, I have owned a few of these over the years and have seen the same fault crop up twice on different machines. The first time round i did not repair as the unit was sold on but I now have one that I would like to repair. The issue appears on both DC and AC power. Looking at the schematic for the PSU there are two regulator circuits. I have visually checked the caps and they look to be okay (not expanded cans) but plan to change them anyway. Wanted to post to see if anyone has had this before with this model.? Issue symptoms: Tape operation always appears to work without issue. However the radio section, sometimes will work, but more often it will power up in what looks like a low power mode... Digital display will be dim or off altogether. There will be no audio. The power meter will be dim or pulsing. Turning the unit off and on many times may result in it powering up correctly. I have attached the schematic of the PSU section. Like I say, I have seen this exact symptom twice myself on two different machines and so this can't be uncommon. Many thanks in advance for any suggestions. Ant.
Hi looking only this part of the schematic ... if you put the switch S101B on the radio it has power only the part of the motor controller ... There must be another section part of the switch S101A somewhere ...
Hi There is another part of the switch detailed but I did not think it was anything to do with power, looks like audio switching. I have attached the PDF I have, S101A can be seen on diagram R240B
So thanks for the schematic ... check if you have this 15 Volt power supply ... which feeds the audio chip and the display chip ...
Thanks for your assistance. It turned out to be Switch101. I soaked it in DeOxit and it started working again. Somehow when switched to phono or radio it was getting some power (around 4v) via another path and few resistors got very hot. Cleaning the switch has restored the functionality Will put it back together and give a good clean, will post some photos as I really like these models.
