MarkT:
7-pin DIN sounds unlikely - what was this connected to ?
I've a 7 pin DIN plug and socket, bought from Farnell/Element14 (order code 1321479 for the plug) about 2 months ago. There are two types. One with 6 pins @ 30o and a central 7th pin, the other with 7 pins in an arc around the edge like the 5 pin audio DIN plugs. NB, these are full size (about 1/2" dia), not mini DIN plugs.