Cliff Jack Wiring

[EddyInChicago]

Hi All,

I'm kinda imbarresed asking this question . However, here goes:
Can someone please explain each lug / pin on a Cliff jack and how it looks
schematically? Please be as detailed as possible. I would like to understand
clearly how it is wired and what the internal workings of it are.

Thank you all,

Edmon

[paulster]

It's more simple than it first looks. The two connectors on one side of the jack connect to the tip and sleeve of the jack plug via the sprung contacts that traverse the socket. When there is no jack plug inserted, they spring down and make contact with the two connectors on the other side, which are known as the switched contacts.

This is how you can have the jack the input to V1a to ground to avoid hum when there is no jack plug inserted by connecting either the switched tip connector to the unswitched sleeve connector, the switched sleeve connector to the unswitched tip connector, or even both of the switched connectors together.

As soon as the jack plug in inserted the switched connectors don't make contact any longer and the only wiring in play is the wiring from the unswitched contacts.

You can also use this for other purposes too. HiWatt wired their speaker jacks such that if there was no speaker plugged into either jack the speaker outputs would be shorted. The idea being that the HT fuse would pop under high current draw but without damage to the OT caused by flyback voltages.

Some foot switches (Marshall Silver Jubilee springs to mind) use a Cliff jack and are wired to the front panel switch connects to the switched side and then when you plug in a foot switch the front panel switch is disconnected and the foot switch takes over, so you've effectively assigned it a higher priority.