RF Audio/ Video Modulator

[ldanto]

HI all,

I'm tryng to build an fr modulator for a freind. I can find schematics for video modulators, but not for audio. Is there any way around this using discrete components

Thanks,

Ldanto
??? ??? ???

 

[Lou1]

Hi

I suppose this modulator is intended to be used with a TV. In this case, all you have to do is to add the sound subcarrier signal (or more exactly, the sound intercarrier signal) to the video signal at the input of your video modulator. The sound subcarrier depends on your country: in Europe mainland it is 5.5MHz, in the US, it is 4.5MHz, etc. You can generate this signal using a small VCO modulated with the audio signal. Premphasis is needed and also depends on the TV standard.
Cheers,
Lou

 

[audioguru2]

Hi Ldanto,
Welcome to our forum.
Dazza has a TV transmitter project with a built-in sound modulator here:
http://www.electronics-lab.com/forum/index.php?topic=2938.0