When I was a kid I always appreciated that my father bought home things he thought would interest me and spur my creativity. These items were usually discarded electronics. Some of them have turned antique over the years such as a late 1930s broadcast microphone from hometown station KRMD. Another less rarified piece is the Electronic Secretary. It weighs a ton and I haven’t plugged it in since the early 70s, but I’ve kept it around because it’s such a unique animal. Can you tell what it is from looking at it?
It’s a telephone answering machine dating from the 1950s. How it works is quite a hoot. That’s a record player on the right side, made to play 45 RPM records. On the left side is a wire recorder (a what?). Wire recorders predate tape recorders. There was some experimentation in the early Twentieth Century with wire recorders. By the 1930s rather good units were being made in Germany. After World War II many GIs brought a wire recorder home. American companies began making them. They didn’t have great fidelity, but were good for dictation. The wire is about as thick as a human hair.
Well, back to how these oddly paired devices make an answering machine. The 90 volt telephone ringing current latches a relay in the Electronic Secretary. This starts the record player. On the turntable is a special record.
It announces to the caller that no one is here and that his/her call will be recorded by a machine—please leave your name and telephone number after the tone. The tone begins. For the caller, it is just a beep. He/she doesn’t know it, but the tone on the record continues for 30 seconds. As soon as the Electronic Secretary senses the tone, it starts the wire recorder and switches the incoming telephone line from the phonograph record to the wire recorder’s record mode. In the background the machine continues to listen to the tone on the record while the caller is being recorded. After 30 seconds the tone stops, shutting down the wire recorder. The telephone line switches back to the record and the caller hears a pleasant good bye and instructions to call back if more time is needed. The machine then hangs up and resets for the next call. As I remember the Electronic Secretary would also reset if the caller hangs before the end of the 30 second record. If your customers were more long winded, you could flip the record over for the same routine but with a 60 second tone.
The Bell System did not allow non-Bell devices on their telephone lines for a long time. There were earlier attempts at answering machines, but it took a while before the public pressured Bell to approve such devices. This one was made by Electronic Secretary for Bell and it originally had the Bell System logo on the front. That emblem was removed before it was tossed out. I expect that this recorder was leased on a monthly basis to a business customer. I remember when I got it running that the recordings were mostly the frustrated Bell Telephone employees who had dug it out of a storage room and tried to make it work. It seems that they were successful in recording, but could never get it to play back.
I’m putting new capacitors in another wire recorder which was made for entertainment purposes. I’ll post something on it in the future.