Low Power Broadcasting with Carrier Current

Carrier Current Broadcasting injects an AM radio signal into a building or neighborhood electrical system. This strategy allow a low power, unlicensed station to broadcast to receivers near the electrical wires carrying the AM broadcasting signal. This can be a simple and relatively inexpensive means to start a radio station where the broadcaster has access to the electrical distribution system. Special equipment is used to connect an AM transmitter into the electrical system for broadcasting.

General information on Carrier Current:
AM Carrier Current Broadcasting from the short-lived Hobby Broadcasting Magazine, Part 1 and Part 2
Carrier Current Broadcasting Theory from the mysterious LPB
Carrier Current Techniques an older but all-inclusive handbook, including transmitter and coupler schematics.
Radio Systems' Carrier Current page

Carrier Current Transmitter Plans
A Simple 2 Watt Tube Carrier Current AM Broadcast Transmitter
Build This: Carrier Current Audio Transmitter
Enhancing the Ramsey AM-25 (for carrier current use) by George Trinkaus
'Part 15' Broadcast Band Transmitter
As always, be careful around electricity!!!