1959 Radio/Intercom

1959RadioTVExp3Sixty years ago, the occasional publication Radio-TV Experimenter carried this interesting project. As the enclosure, it used an already antique crank-type wall telephone as the housing for a radio receiver, but put the telephone back into service as a home intercom.

According to the magazine, the phone was rapidly vanishing from the American scene, and interior decorators had been busy snatching them up to convert into spice cabinets, pin-up lamps, and liqueur chests. Instead, the magazine showed how to preserve the original communication function by providing an intercom between floors of a house, between house and garage, etc.

The radio function was added by use of something found in almost every home, “a small table-model radio set of the ac-dc type that has been set aside because of a broken cabinet, missing knob, or a minor circuit defect.” Such a radio was squeezed in, with the controls mounted under the phone’s writing desk.

Obtaining the phone was a matter of ordering one from Telephone Repair & Supply Co. of 1760 W. Lunt Ave., Chicago, where it was available for $7 plus postage for the 20 pound instrument. Most such surplus phones came with the crank, but not the magneto, since apparently the phone companies still needed some of those for their rural customers.  The phone will have been in service for fifty years, so the article gave details on how to refinish the wood and metal components.

The article next explained how to wire the phone back up. Even without the magneto, the ringer could be made to work by including a button on the side of the phone (where the crank used to be), wired to the bell through an induction coil. Presumably, the phone would ding once when the button was depressed. A three wire circuit (or two wires plus ground) was used to hook the phones together, with one wire for the voice connection and one for the ringer. The wiring diagram is shown here:

1959RadioTVExp4