• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Pioneer SX-680 no tuner - help!

Krosya

Krosya

Well-Known Member
Hi All,
I got this nice little receiver in a trade and everything works fine, but the tuner. No AM or FM. I did some digging online and there was a thread or two here that points to something called Q401. I am not very savvy when it comes to these things internally, but if someone could point this Q401 to me - maybe I can figure it out. I dont really know how to read schematics, but if someone has a photo of the board with this Q401 marked, so I know where to look and tell me how/what to test on it - I would really appreciate it. Thanks!
 
Register to hide this ad
With what you know, please do not attempt to repair that receiver. Wait until you can get help from someone who has more knowledge. I just got in a receiver from someone who attempted to repaired it himself. He tightened down all the ferrite slugs in the AM FM tuner until they broke apart. The slugs could not even be replaced because the broken slugs had ruptured the internal transformer windings. Now it is just an amplifier. You need to have a scope to find out where the signal is stopping. The power supply to the tuner might even be dead. It could be anything. I am sure I live far from you and cannot help you myself. I live in the upper peninsula of Michigan.

Troubleshooting electronics is not alway very easy even for people with experience. Wild guessing a "fix" has ruined a lot of equipment.
 
check soldering on q401 first as it might be that .
original is 2sd712 and can be replaced with MJE15032G
 
Well, that's the thing, I don't know what it looks like and where to look. Do you have a photo of it?
 
s-l640.jpg
 
There's corrosive glue and fusable resistors that have killed the tuner in multiple SX-680's I have worked on right next to that pass transistor. Best to clean and replace everything in that area and it should come back to life.
 
You must log in or register to reply here.
Back
Top Bottom