Thanks for the reply.
Yeah the AC switch was engaged. Looks like that was only a small problem. I've now got voltage to pin 7. Still no joy on a reading though.
I've tracked an AC single into U8 using a scope, and followed it around the board. Unfortunately there are no schematics for that board so I don't know what I'm looking for.
I think I might be stuffed for AC unless I can find a replacement U8 board. If anyone out there might be able to donate one - that would be amazing.
If anyone is interested the chips on the board are (from right to left) are LF351n, 7849, CA3049 and a LF351n.
Cheers