And for that matter the 3-pin DIN plug will fit said socket. This explains the strange pin numbering of these sockets (for the 7 pin it's 6 1 4 2 5 3 7 rounf the arc, on the 8 pin it's the same with pin 8 in the middle, etc) You start wit he 3 pin plug, which has the pins 1 2 3 in the obvious, sensible, order. The 5 pin added pins 4 and 5 between them. The 7 pin added pins 6 and 7 on the ends. The copatibility is intentiona./ The original use of this connector was for audio applications, for a mono tape recorder socket. Pin one was the output from the radio (input to the tape recorder). Pin 2 was ground. And pin 3 was the input to the eadio (output from the tape recorder). For stereo. the 5 pin plug was used, pin 2 remained earth, pins 1 nad 3 kept their old functions for the ledt-hand channel ,while pins 4 and 5 were the corresding functions for the right-hand channel. There are actually 2 other 5 pin DIN connectors. The one we've been talking about is commonly called 'type A' or '180 degree'. There's a 'type B' or '240 degree' that has a similar compatability with the 6 pin connecotr, and those were originally intended for 'non audio signals', for example PSU inputs to a battery tape recorder/radio, remote controls, slide projector control, etc. And there's the 'type C' or '360 degree' or 'Quincuncial' that was sometimes used for headphones. There's also an 8 pin version with the 2 pins at the end of the arc offset. It's incompatible with the normal 7 and 8 pin plugs (although AFAIK the 3 pi nand 5 pin plugs will fit). I've never seen an analagous 7 pin connector. AFAIK _all_ have been sued somewhere on classic computer equipment. -tony

On Wednesday 08 August 2007 18:11, Tony Duell wrote: True, but it's been a really long time since I ran into one of those... First time I saw these connectors was on the back of a radio my mother bought in Germany in 1960. :-) I knew that there was at least one other variant. And then there's that "mini-" stuff that seems so prevalent these days. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

So do I. One of the worst jobs I ever had to do was 'edit' the wiring on a 9 pin Mini-DIN. I don't know why they're so widely used [1]. The don't (IMHO) make reliable contact, the solder-type plugs are often too large to fit into a socket that was intended for a moulded one, they have nothing to recomend them. [1] Equally I don't see this love of making everything so darn small in the first place. A _little_ larger (say using full-size BINs rather than mini-DINs) would make no difference in almost all cases. Where I can, I buy the plug-to-open-end cables (or plug-to-plug and cut them in half) from companies like RS components. Expensive, but it saves a lot of four-letter words... -tony