Jacks with N.C. Tip and Sleeve, N.O. RIng

idy · Post by **idy** » 03 Jul 2015, 20:25

: jack.jpg (23.76 KiB) Viewed 779 times

These are like Neutrik, but not in their catalog. The Sleeve and Tip have the usual normally closed switch, but the ring is normally open. Mad Professor uses them. Any ideas where to find them?

Lucifer · Post by **Lucifer** » 10 Jul 2015, 14:15

You should be able to pull the ring tab ‘inner’ contact from under its corresponding ‘outer’ tag and leave it hanging above said ‘outer,' so that instead of ‘breaking’, it ‘makes’ when a jack is inserted. I think that is what has been done here (ie, in the picture). It also looks like the leg of the ‘inner’ had been pulled out a bit to allow a space between the two contacts - but not enough to make the solder pin unable to reach the board solder pad (obviously).

idy · Post by **idy** » 10 Jul 2015, 17:58

Thanks. I thought that also, and there may be a way to make that work... It would have been most elegant for the manufacturer to make it so, a user configurable N.O./N.C. jack...
But the actual piece of metal on the ring "switch" is clearly different in shape than the others, it narrows at the end. And the ends that go through the pcb are all full length The terminal could maybe be replaced, but bending the existing piece it's pretty brittle and won't allow "working" before it breaks.
Somewhere in a factory there are boxes of these terminals....

It seems to implement the usual "ring to ground" power switching but with an extra part. The negative from the jack/battery goes to the lower terminal, which the plug pushes up to touch the grounded upper terminal.

It's a Mad Professor Golden Cello. Some/many of the other newer MP pedals use these.

I doubt I'll ever have to replace one of these, but I am curious. And what else might this be useful for.

deltafred · Post by **deltafred** » 10 Jul 2015, 21:10

Lucifer wrote:You should be able to pull the ring tab ‘inner’ contact from under its corresponding ‘outer’ tag and leave it hanging above said ‘outer,' so that instead of ‘breaking’, it ‘makes’ when a jack is inserted. I think that is what has been done here (ie, in the picture). It also looks like the leg of the ‘inner’ had been pulled out a bit to allow a space between the two contacts - but not enough to make the solder pin unable to reach the board solder pad (obviously).

I have done this in the past and it works well.

I have also made a bracket and positioned a sub-miniature micro-switch above one of the contacts so it is closed when the jack is inserted (long time ago and I cannot even remember why I needed a completely isolated switch).