On a normal switchcraft jack like you get in a MOTM kit, you have 3
terminals:
ground
hot
normal
This is called a "normalling" or a "switching" jack.
Ground is the terminal on the beveled corner and you can look inside
and see where it connects to the sleeve.
Looking from the back (terminals side), the next jack counterclockwise
is the normal terminal. More about that in a moment.
The next one CCW is the hot terminal. This one always connects to the
piece that touches the tip of the jack when plugged in.
The normal terminal is special - it touches the hot terminal when the
jack is empty, but gets disconnected as soon as you plug something in.
Normalling terminals are only used for module inputs, never outputs.
They are useful when you want to apply a signal at that jack that can
be overridden with a patch cable. MOTM modules use normalling jacks
everywhere, but the normalling terminal is rarely connected. Here's a
couple of examples where it is:
In the MOTM 101, the internal clock is normalled to the S&H thru the
CLOCK IN jack. You can override the internal clock to use an external
clock source by plugging into that jack.
In the MOTM 300, the 1V/octave voltage control input jacks are
normalled to ground, to keep the pitch control input from drifting
when nothing is plugged in.
The ability to normal is one of the big advantages of 1/4" systems
over banana systems.
Moe
--- In motm@yahoogroups.com, "brownchonald" <chonald@...> wrote:
>
> i was wondering if someone could help me out.
>
> my problem is that i'm not exactly sure how to tell apart the
> different terminals on a jack socket.
>
> i know there is a tip, ground, and something else.
>
> but, compared to a diagram of one, and an actual socket, how can i
> tell the difference between these three?
>
> cole
>