USIC Sound Powered Handset

[Craig T]

Thanks again Grandpa! This was wired to a long appliance cord for some reason or another.It has brass rings, a brass center plate and the spit cup. It says

United States Instrument Corp.
Summit, NJ. USA
DW(I or R) No. A-257 ALT.-2
Sound Powered Handset


I think this is it here. http://www.freepatentsonline.com/D356315.html


Here is a great description of how a sound powered set works. It is part of a US Navy training course. See section 1-1 Operation of Sound Powered Telephones

http://compass.seacadets.org/classroom/reading_room/navy/14232.pdf

It is the 12th page if you count it off, it will say 1-1 at the bottom of the proper page.

Anyone ever use one of these?

[Jim Stettler]

I have a set of them somewhere. An Electrician put plugs on the ends for talking over dead electrical circuits. (not a safe idea)

Electricians sometimes use a pair of G handsets w/ a battery to provide an intercom path for long wire runs.
You find a common wire and clip on 1 side. One guy picks another conductor and the other guy tries to find it. Once it is found and Tagged, you move on to the next conductor.

I have given several sets of handsets to electrician friends for this purpose.

Jim S.

[Wallphone]

This is the best site that I have seen on sound powered.
> http://www.crystalradio.net/soundpowered/ <
Dougpav

[Craig T]

I read somewhere while searching that Stromberg Carlson bought out USIC later on. This handset looks just like the one listed under Stromberg Carlson.