[AMRadio] Carrier Current Devices

[Mike Duke, K5XU]

Early "wireless" intercom units actually used carrier current. If you and 
your neighbor had the same intercom equipment, and were on the same service 
transformer, things could become interesting, as you had an instant 
"listening Tom" in each other's houses.

The units I played with transmitted somewhere in the lower 400 KHZ region, 
but their signal was so weak that I could barely detect it in a traditional 
receiver.




Mike Duke, K5XU
American Council of Blind Radio Amateurs