hello

could anybody give me a carrier current transmitter and receiver circuit ? i want to transmit audio signal through power lines (via mains ac 220v). or please tell me how to inject RF energy(modulated signal) into (220v mains) power supply lines and also how to demodulate the same.my only problem is dealing with power lines. any resources / books on the above topic is appreciated.

 

Go to National Semiconductor's site, and download Application Note 146 -
or click here: http://www.national.com/an/AN/AN-146.pdf
It's a remote FM speaker system using an NE566 VCO/function generator and NE565 PLL Detector using household mains wiring.

Neither of those ICs are in production anymore, but you may be able to substitute other components. It's the theory you're looking for.

 

if i simply take a battery operated fm transmitter and couple it to the mains using a .1uf 250v capacitor, will it be able to inject rf energy into mains? can i receive it using receiver kept close to power line? then, will there be any mains hum in the receiver?