Jonathan K
New Member
Just wanted to say a heartfelt thanks to the collected knowledge here on AK. Using the information on these forums, I was able to successfully restore a Sansui AU-7900 that was experiencing periodic pops and clicks - bad enough that the protection circuit would kick in.
Final restoration involved:
- Re-cap including power filter capacitors
- Replacing the 2SA798s with matched pairs of KSA992FBs
- Replacing the bias trim pots with Bourns 3329H-1-501LF
- Replacing the fusible resistors with 1/4W metal film
- Replacing the VD1212 diodes with 1N4148 pairs
Amp is now working properly and comes out of protection much more quickly on power-on. Unfortunately this one is going back to it's owner so I don't get to keep it. However, I did also get my Technics SA-5170 tuned up at the same time.
So thanks again. Troubleshooting this would have been a much longer process without the suggestions on this forum.
Final restoration involved:
- Re-cap including power filter capacitors
- Replacing the 2SA798s with matched pairs of KSA992FBs
- Replacing the bias trim pots with Bourns 3329H-1-501LF
- Replacing the fusible resistors with 1/4W metal film
- Replacing the VD1212 diodes with 1N4148 pairs
Amp is now working properly and comes out of protection much more quickly on power-on. Unfortunately this one is going back to it's owner so I don't get to keep it. However, I did also get my Technics SA-5170 tuned up at the same time.
So thanks again. Troubleshooting this would have been a much longer process without the suggestions on this forum.