Pioneer SX-870 Receiver (Broken trimming resistor)

Hi All!

First off, let me say I'm a newb when it comes to repairing these, but I'm working on expanding my knowledge to become better (My apologies in advance).

I have an old broken Pioneer SX-780 that I got a decade ago, that's been on the backburner on getting fixed up until now. Taking a look inside, it does look to have some water damage, and bunch of capacitors were blown. Which is a bummer, because the outside case looks almost mint. Just need to clean the dials from some light dirt. Pretty ironic that the outside case is excellent, but the inside bad..
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There's some rust and corrosion inside, which I've cleaned a lot of it off the board and most of the components. I replaced almost all the capacitors and now, I got the receiver to boot, and clear protection mode. One of the channels doesn't work at all though. I went to go adjust the the DC offset on the board, and one of the trimming resistors just fell apart. I'm trying to find a replacement for it, but I'm a bit overwhelmed trying to find the right part. Any help would be greatly appreciated!

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Taking a look at the service manual, I believe this is the part. Could someone help me find a part? Many, many thanks in advance!!

Part No. Symbol Description
ACP-014 VR5, VR6 Semi-fixed 150k

This is the part I need to replace Here:
broken dc switch.png


Best,

Nater
 
Well, I think I just answered my question. I found and ordered two replacement trimming resisters. I'm going to replace both, so they match. Hopefully will be more stable. I think these are the right size, and I was able to match the resistance. I'll post an update, after I tried replacing. Hopefully this fixes one of my issues... 🙂

I bought 2x Mouser 652-3329H-1-154LF

Termination Style: PC Pin
Product: Single Turn
Number of Turns: 1 Turn
Resistance: 150 kOhms
Adjustment: Top Slot
Power Rating: 500 mW (1/2 W)
Voltage Rating: 300 V
Tolerance: 10 %
Temperature Coefficient: 100 PPM / C
Orientation: Vertical Adjustment
Minimum Operating Temperature: - 55 C
Maximum Operating Temperature: + 150 C
Packaging: Tube
Brand: Bourns
Diameter: 6.35 mm
Element Type: Cermet
Height: 4.57 mm
Mounting Style: PCB Mount