[GreenKeys] Strange double plug

[Jeffrey Angus]

On 6/6/2011 2:29 PM, Jim Haynes wrote:
> The plug connects only to the sleeve terminals of the jacks!  The plugs
> are solid brass nubs that don't reach far enough into the jacks to
> contact the tip contacts.
>
> The origin appears to be Western Union.  I sure can't imagine what kind
> of circuit would make use of a plug like this.
My guess, and I'm sure if I'm wrong someone will kindly point
it out to me. ;-)

The "double plugs" are normally set up with RX on both ring
connections and TX on both tip connections. The reason for
this being then it doesn't matter which way you plug them
into the jack pair.

That green "test cord" you bought has the short plugs so it
only hits the two ring connections.

And going out further on the limb, this is for "supervisory"
listening (or checking) RX levels.

After all, this _is_ the phone company, you're NOT supposed
to go "No shit?" And start laughing if the customer says
something really goofy.

Jeff-1.0
wa6fwi

Operators are standing by for corrections. ;-)