What is the "pinout" for these jacks?

[Effectsiation]

Sorry, I know pinout is not the correct term, but I can't think of it right now.

Anyway, I foolishly bought from Mammoth Electronics a bunch of economy jacks and their 1/4" Mono Jacks have three lugs?!?

Does anybody know what is Tip and what is Sleeve here... or are there 2 Sleeves? or 2 Tips??!? I dont know I'm way confused, here's a picture:

http://image.zlectronic.com/stock/laptopparts28/100_199/14316_7.jpg


Mammoth confirmed that these are not just weird looking stereo jacks and infact the mono jacks.

[rowland1]

I made the same mistake and have 10 of these. Curious to know what that third lug is for.

[jkokura]

They are switching jacks. What happens is before you insert a plug into the jack, two of the lugs will be in contact with each other, then when a plug is inserted that connection will be broken.

Left side jack with the three lugs visible: (Left to Right) Tip - Switch - Ground.

At least that's what it looks like from here. Only certain way is to actually test it myself.

Jacob

[JakeFuzz]

Its an NC jack. NC stands for normally closed.

If you look at the piece of metal that contacts the tip you'll see that it has a "leaf" type switch that contacts its length. Look at it closely when you put in a guitar cable. You'll see that as you insert the cable it will lift the tip metal until it no longer contacts the inner leaf; so it is a switch that is controlled by inserting a cable. The other lug is what the tip connects to when there isn't a cable in the jack.

These are particularly useful for effects loops and expression sends. Things that aren't necessarily connected all the time during operation but you would like a change in the circuit when they are attached. You can use them like normal jacks, just don't connect the third lug.

Hope that helps.

EDIT: Jacob beat me to it 

[Effectsiation]

Thanks Guys!!

[oldhousescott]

[jkokura]

See, that's what I mean. Without the jack in my hand I can't tell as well.

For anyone searching - you can follow the connections between the lugs and the contacts much better yourself then we can. If you need to, use a multimeter and a plug and see which lug connects to which part of the plug.

Jacob

[bigmufffuzzwizz]

I just finished up the bulk of those economy jacks from Mammoth I bought awhile back. I just break off the lugs with the heavy teeth from my wire strippers..like Jacob said you follow the metal connections and you can see what each lug is for. The stereo jacks are even crazier with 4 lugs, I'd probably never buy those again since I don't use batteries anyways.