PIONEER SX-950 RECEIVER HELP....

[EBYDRE12402]

HAS ANYONE FIGURED OUT YET HOW TO FIX THE SPEAKER CUTTING OUT PORTION OF THE PIONEER SX-950?....I BOUGHT THIS MACHINE IN A USED SHOP FOR $10.00....EVERYTHING WORKS BUT THE SPEAKERS CUT OUT....IT PLAYED FINE FOR A FEW MINUTES, THEN CUT-OUT THE SPEAKERS 3 DIFFERENT TIMES, AND NOW WONT COME BACK ON....ANYONE KNOW HOW TO FIX THIS?....THANKS FOR ANY HELP....
_________________
THANKS FOR YOUR HELP,

JOHN.

[Baeteman]

Hi there,

as to my opinion, you're having a prob. with DC offset in one of
the final stages, causing the protectioncircuit to trip.
When it switches off the speaker, try to measure the voltage
at the common ouput point from each final stage.
The voltage there should be around zero volts.
If not, the fault should be found in that final stage.
Look for "dry" solderingjoints. Cool down the transistors (pre-drivers
drivers, final ones) with "cold-spay", and observe the voltage.
If there is a termal problem with one of them, you see it rightaway.
Unfortunately I have no diagram otherwise I could give you some
more hints about it.
Important: NEVER force the protectionrelay on with speakers connected.
This will deteriorate one of them, including the faultly finalstage !

Good luck and kind regards.

[cobra562]