camtarn
4 days ago
I was wondering how they managed such an impressive signal fan-out - I thought that telephones at that time were purely powered by acoustic energy moving the coil in the microphone. Turns out that the amplifying telephone repeater had just been invented a few years previously, enabling transcontinental phone calls and - in this case - splitting a signal to be played in many places.
It must have been an incredibly exciting time to be alive.
Aloha
4 days ago
Bear in mind, before this there was a mechanical repeater as well, which was a transmitter and receiver which were mechanically coupled.
A carbon mic is somewhat self-exciting and does provide an amplification factor.
camtarn
4 days ago
Aha! For some reason I had it in my mind that early telephones were moving coil type, and the carbon mic came along later. You're absolutely correct - thanks for setting me right.
Aloha
4 days ago
Its really an ingenious device, I've wanted to build one, just because I'm a phone nerd, think its cool.