Goin crazy on sx-680...

I came looking for you josemalicdem, found you this forum, not the "ask the Pioneer Audio forum" I recommended.

Welcome to AudioKarma. I came LOOKING for you... please ask in the Pioneer Audio forum, you posted in solid state which may not see as much helpful traffic.... PLUS you stomped right into on an ongoing troubleshooting session. I MEANT "start your own thread in the Pioneer Audio forum." I didn't type it for the exercise...

I can understand the confusion between posting in private conversations and public conversations in the forums.

So < with a BIG smile> you are forgiven.

in your NEW THREAD: You need to describe everything you have done to the unit, in that post - finding out that you have replaced the module is VITAL info.

First thing, you need to take some DMM readings, for the +45v regulated DC, the +13.6v regulated DC, the UNREGULATED +34.5v dc, -34.5v dc of the main capacitors, the -33.3v on both sides of R410, the special zener regulated +13v in the power amps derived from the +45v regulated DC through R348 and D309.

All these voltages help balance out the power amp for correct operation. Unbalanced swings the output voltage of the amps towards either power "rail".

To do that you need a DMM and a download of the service manual.

Others can help point you towards finding those voltage points.

I'm out of time today.. I stole THIS time from something else IMPORTANT.
 
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Well..I am trying to figure out what is wrong with mine..I have no sound in right channel. I will take sum voltage readings and list them today
 
I'm guessing that Pin 2 on that first module is actually -31V, or it should be.

27V and more on Pins 0 and 1 of that first module (Q2) is a bad sign, potentially indicating an E-C short in that side.
 
Personally, I would remove the suspect module and test it, and not risk burning up a second one.
 
I'm guessing that Pin 2 on that first module is actually -31V, or it should be.

27V and more on Pins 0 and 1 of that first module (Q2) is a bad sign, potentially indicating an E-C short in that side.
E -C short..? That means ? Emitter-Collector?
 
Yes, emitter-collector. Look at the pinout diagram for a STK-0039 and notice the external connections for the transistors. Resistance measurements between pins 1-2, 2-3, and 0-9, 8-9 could be an indication.
 
I have a dc offset in the right channel of 29.8V !! Wtf ? Left channel is 17.0 mv..I think that's fine but..idk why its jacked up like this on the right ch
 
If the right channel output module has an internal short, the DC bus (rail) voltage would be connected to the speaker terminal.
 
update!!!! I am not sure what I did..but I installed the "new/fake" 3009 in and now the right ch meter is pegged halfway across the board
 
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