Hello!
I have an old Yamaha RX-500 receiver that I am trying to repair. The symptoms are as follows:
The service manual is on ManualsLib here: https://www.manualslib.com/manual/1287625/Yamaha-Rx-500.html#manual I have also attached it. I had to .zip it as it was too large to attach otherwise. The schematics begin on page 14. I currently have the whole unit taken apart as I was testing the capacitors with an ESR meter and can't find any bad ones so far. I have access to an oscilloscope, DMM, and an ESR + LCR meter...all the gear, and no idea perhaps?
If anyone can suggest some troubleshooting steps for me, that would be most appreciated.
I have an old Yamaha RX-500 receiver that I am trying to repair. The symptoms are as follows:
- Unit powers up OK and I hear a relay click inside. The LED for the 'CD' input on the front of the unit is always lit, irrespective of my current input. For example, if I select 'Video', the 'Video' LED is lit and the 'CD' LED is also lit but it is a bit dimmer. If I press the 'CD' input button, it lights up as per normal and the previously select input's LED turns off as you would expect.
- If I plug my phone into one of the inputs (e.g. Video), I can play sound but it is very low volume and does not sound healthy - furthermore, if I choose another input while plugged into Video, I can still hear sound coming out of the speakers.
- The last symptom is that I am measuring 7 volts DC on the CD inputs at the rear of the unit. I found this out when I initially got the unit and tried to plug my smartphone in to play some music, I chose the CD input and my phone switched off immediately (I guess it was protecting itself, thank goodness). I measured the other inputs and they don't have this high voltage - nowhere near it.
The service manual is on ManualsLib here: https://www.manualslib.com/manual/1287625/Yamaha-Rx-500.html#manual I have also attached it. I had to .zip it as it was too large to attach otherwise. The schematics begin on page 14. I currently have the whole unit taken apart as I was testing the capacitors with an ESR meter and can't find any bad ones so far. I have access to an oscilloscope, DMM, and an ESR + LCR meter...all the gear, and no idea perhaps?
If anyone can suggest some troubleshooting steps for me, that would be most appreciated.
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