That's brilliant news. I may be able to help. There was an auction on eBay in the US for the amplifier modules from an M10, and from the photos posted I have traced *part* of the wiring of the M10 program plug.

The M10 amplifier socket, is a 5 pin DIN socket, and is wired as follows (pins numbered 1-4-2-5-3, left to right, facing the socket)

Pin 1 - not connected
Pin 4 - red wire, which connects to the crossover
Pin 2 - not connected
Pin 5 - green wire, which connects to the crossover
Pin 3 - not connected
Screen - looks like the screen is connected to the chassis ground

One option is that pins [4,5] are wired [high,low] to give the three program plug combinations and one for no plug. But there may be some circuitry inside the program plug ...

Good luck

I do have the copies of the M10 amp photos. PM me if you want them. (I didn't take them, so I can't just ask Duncan to post them).

- Zygmunt

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