Help! Pioneer Sx-1250 No sound, Indicator lamps, tuner etc.

Jcatsweeney

New Member
Looking for some help here... My SX-1250 is almost dead, When I power on I have illumination lights and that's about it. I'm starting with the AWR 106 power supply assy. I have taken some voltage readings and here is what I currently have.

Pin / Actual / Svc manual says I should have
#1. -66 / -62
#2. 66 / 62
#3. 0 / ground
#4. 0 / 0
#5. 0 / 0
#6. 85 / 85
#7. 23 / 23
#8. 0 / 5.4
#9. 0 / 13.5
#10. -5 / 25
#11. 84 / 65
#12. 0 / ground
#13. -63 / -63
#14. -23 / -25
#15. -86 / -87.5

I am thinking I should start by rebuilding this board. Pins 8 through 11 are obviously incorrect. the board appears to be all original. I'm new to electronics so any help or advice would be appreciated.
 
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Let's start off by doing this, give me the dc voltage on the collector of Q4, and the collectors of Q9 and Q10 and the collectors of Q12 and Q13. Check the resistance of R13 680 ohm 2 watt, R17 3.9 ohm 1/2 watt and R18 100 ohm 2 watt. Check D5 zener diode and check D6 for short or open. Also check D1 and D3 zener diodes for short or open.
 
You can remove the 106 PS board and reconnect it on the bottom of the receiver. The receiver has to be on it's side with the right side to the top. Sandwich a thick rag between the hanging Stabilizer board to prevent any contact/shorts to the bottom boards and components. This will give all the access you need to the voltage points.
The readings on pins 4 and 5 are in AC for the unregulated supply to the outputs. Probably not the issue but you should know there is AC running in that board.
 
Let's start off by doing this, give me the dc voltage on the collector of Q4, and the collectors of Q9 and Q10 and the collectors of Q12 and Q13. Check the resistance of R13 680 ohm 2 watt, R17 3.9 ohm 1/2 watt and R18 100 ohm 2 watt. Check D5 zener diode and check D6 for short or open. Also check D1 and D3 zener diodes for short or open.

I am realizing that repairing this beauty this is beyond my capabilities at this time. I appreciate your response and willingness to help me out. Is there someone here that I can send this board to? or perhaps someone in NC/SC or eastern TN that I could bring it to? Jay
 
Every SX-1250 I touch in the Carolinas ends up following me home, and into my rack.

Frankly, given the interconnection of the power supply, stabilizer, and other parts of the system, it would be far better to get the entire unit into service. A brand-new (if it were available) PS board might exhibit the same or very similar symptoms if something else in the unit were overloading it.
 
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