What are these jacks called?

[Chris Veitch]

I have an old (but good) AGW power unit from around 1980. It has 1 x 12V DC and 1 x 16V AC outputs on the back. These are holes of about 3.5mm in a sheet of laminate insulator which take "split-pin" type connectors. The original connectors were lost years ago and I currently use - well, cut down split pins. The ideal minimum diameter of the pin seems to be 3.0mm.

This isn't elegant and I'd like to use "proper" connectors but there seems nothing suitable in the usual electronics suppliers such as Maplins etc. Does anyone know:

i) What these connectors are called?
ii) Where they can be obtained?

Thanks

Chris

[Graeme Dunbar]

Other than the mention of 3 mm diameter, they sound like 4 mm "banana" plugs as they are very commonly found on "laboratory" power supplies. They come in various designs and some of them do have metal prongs that look like split-pins. Others have a sprung wire running the length of the pin and yet others have metal shim "wings".

Try here:
http://www.rapidonline.com/Cables-Connectors/Connectors-Single-Pole/4mm-Connectors/4mm-Banana-plug/125053/kw/banana+plug

http://www.rapidonline.com/Cables-Connectors/Connectors-Single-Pole/4mm-Connectors/4mm-Banana-plug-to-4mm-straight-socket/400360/kw/banana+plug

[Chris Veitch]

Other than the mention of 3 mm diameter, they sound like 4 mm "banana" plugs as they are very commonly found on "laboratory" power supplies. They come in various designs and some of them do have metal prongs that look like split-pins. Others have a sprung wire running the length of the pin and yet others have metal shim "wings".

Try here:
http://www.rapidonline.com/Cables-Connectors/Connectors-Single-Pole/4mm-Connectors/4mm-Banana-plug/125053/kw/banana+plug

http://www.rapidonline.com/Cables-Connectors/Connectors-Single-Pole/4mm-Connectors/4mm-Banana-plug-to-4mm-straight-socket/400360/kw/banana+plug

Thanks for that Graeme. I think I've tried these previously and found that they don't fit by a frustratingly small margin. Unfortunately the dimensions seem to be fairly critical and don't allow for much "split" in the split pin. I suspect that whatever AGW used may be a bit arcane and probably obsolete by now, not to mention primitive.

Regards,

Chris

[JulienW]

Other than the mention of 3 mm diameter, they sound like 4 mm "banana" plugs as they are very commonly found on "laboratory" power supplies. They come in various designs and some of them do have metal prongs that look like split-pins. Others have a sprung wire running the length of the pin and yet others have metal shim "wings".

Try here:
http://www.rapidonline.com/Cables-Connectors/Connectors-Single-Pole/4mm-Connectors/4mm-Banana-plug/125053/kw/banana+plug

http://www.rapidonline.com/Cables-Connectors/Connectors-Single-Pole/4mm-Connectors/4mm-Banana-plug-to-4mm-straight-socket/400360/kw/banana+plug

Thanks for that Graeme. I think I've tried these previously and found that they don't fit by a frustratingly small margin. Unfortunately the dimensions seem to be fairly critical and don't allow for much "split" in the split pin. I suspect that whatever AGW used may be a bit arcane and probably obsolete by now, not to mention primitive.

Regards,

Chris

Might they be an imperial size?  1/8 th inch is not far off 3 mm (3.175 to be exact) so might that be the issue?

Not sure if I can help finding a source though Chris.  What about making some 'jacks' from 1/8 th" brass rod, or sleeving some babana plugs?

[Graeme Dunbar]

Thanks for that Graeme. I think I've tried these previously and found that they don't fit by a frustratingly small margin. Unfortunately the dimensions seem to be fairly critical and don't allow for much "split" in the split pin. I suspect that whatever AGW used may be a bit arcane and probably obsolete by now, not to mention primitive.

Regards,

Chris

That's a pity. If you have no luck finding replacement plugs, is replacing the sockets with 4 mm ones a possibility? You'd be sure then that standard "test leads" would fit it.

Failing that.... bare wires and matchsticks!  :o

[Chris Veitch]

Thanks for that Graeme. I think I've tried these previously and found that they don't fit by a frustratingly small margin. Unfortunately the dimensions seem to be fairly critical and don't allow for much "split" in the split pin. I suspect that whatever AGW used may be a bit arcane and probably obsolete by now, not to mention primitive.

Regards,

Chris

That's a pity. If you have no luck finding replacement plugs, is replacing the sockets with 4 mm ones a possibility? You'd be sure then that standard "test leads" would fit it.

Failing that.... bare wires and matchsticks!  :o

Yes, it's a possibility if I drilled out the rivets holding the case together. But since we're all (mostly) grown-ups it should be OK if I'm careful...

Regards,

Chris

[ian]

H&M used something similar which were called 'Wander Plugs' IIRC. They seem to have disappeared from the market place.

[Graeme Dunbar]

Wow! Well remembered Ian. Typing "wander plug" into Google suggests that vintage radio enthusiasts have similar difficulties finding replacements. Chris is not alone!

[Chris Veitch]

I have an apology to make. I thought I'd tried banana plugs but when raking out all the old bits and pieces and comparing them to the stock in Maplins, it appears that I user the rather posher-looking 4mm plugs (the solid brass ones with the two slits - a bit like 0mm sized collet). I bought a few banana plus and even though they're nominally 4mm they will fit - if you shove them in hard enough - even though the holes are mysteriously all different depths and all the plugs stick out at different angles!

Thanks to everyone anyway...

Chris