Wanted pin-out for Blackstar/Marshall 7-pin pots

[microbailey]

Hi everyone. I'm dismantling and tracing a Blackstar Fly 3 amplifier (see thread here: viewtopic.php?f=2&t=30681 and here:http://www.midboost.com/workbench/blackstar-fly-3) and I am looking for the pin-out for the 7-pin PCB pots used by Blackstar - pictures from above and below PCB follow:

I know this is a dual gang (tandem) pot and I think it is the same pot used by Marshall for Master Volume in some modern amps (DSL 401 ?)

Does anyone have a pin-out for this pot?
I have a feeling one pin is a dummy leaving 6 pins for the 2x tandem pots.
I could desolder a pot and then resistance test but thought I'd ask here first.

I did find the Bourns pot range which matches what Blackstar use, but no 7-pin tandem I'm afraid.

[ppluis0]

Hi microbailey,

Try this pin assignments and see if make sense in your tracing:


Cheers,
Jose

[microbailey]

Aha! Yes that looks promising. I'll plug it into the schematic I have so far and see if it makes sense.
After a bit more research I think the pots are Alps not Bourns.

Thanks Jose

[microbailey]

I tried the pinout suggested by ppluis0 in my traced schematics and it fits. This is confirmed using a multimeter to measure resistance between the 7-pins, assuming the pinouts given in https://sc01.alicdn.com/kf/HTB1HJD8vLiS ... DcpXa7.jpg.

Searching the web I also found

Alps_7pin_pot.JPG (19.19 KiB) Viewed 1415 times

on the Apls website - which agrees with ppluis0

Thanks for that - I can press on with tracing the Blackstar EQ section now I now how these 7-pin pots are wired