Pioneer SX-1050 has a dead channel

[audiocrzy]

That board is a pita to get out. Might as well do everything that is recommended. I would like to fix the channel before I start making wholesale changes. That way lies madness.

Definitely stay with that mind set. Don’t replace any parts that don’t directly address the current problem. It will save you a lot of possible grief.

 

[merlynski]

I had the heatsink and the board swung out from the chassis during rebuild and post-rebuid testing, supported on the turntable with vises:



I could easily make measurement and adjustments, and quickly replace parts without massive reassembly and disassembly.
In this picture I am monitoring dc offset on both channels, on the power amp output pins, at the same time (using two meters).

Here is again a pic of the backside of the power amp board without the heatsink and output transistors connected:


Easy access for troubleshooting and parts replacement without risk of dropping anything into the chassis during rework or power up testing..

My turntable came from Amazon, and it was barely big enough for the SX-1050. I wish I had a bigger one.

 

[Rob357]

Dear Rob357 how can i get this Rotary Table ?

If you have not found one. Here is the link.
https://www.amazon.com/gp/product/B07BVXLSVN

 

[Mac_DD/DC]

Thanks Rob357, Anybody know what paint is good for this type of Heat-sinks, I try with "Car Brakes Caliper Paint" what do you think ?

 

[merlynski]

It looks like plain enamel paint to me. If I was going to repaint I would be tempted to use automotive radiator paint, goes on as a thin coat and is heat conductive. If I went really OCD on it I might consider bead blasting it first, then black anodizing.