Please help me find a good FM transmitter schematic

Hello everyone. I searched the nets but did not find anything that fits my needs.
I need to build myself an stable stereo FM transmitter that is capable of delivering good audio quality in the 87-108 Band and digital controlled + LCD.
I have a few schematics of such devices but they are mostly old designs and i cannot find specific ICs anymore.
Power is not important since i have a 100W linear RF amp at my disposal.
Thank you.


2010-03-11 10:43 pm
Years ago I built a stereo multiplex generator, solid state, that worked fine. It used a 19 kHz crystal. It's a simple matter to use the output of such a unit to modulate an oscillator and achieve FM suitable for radiation.

One thing to do is make sure you are not violating any rules, regulations, or laws concerning building and using a transmitter. Here in the US there are limits on how much power is to be used without a license. And with a license, equipment must be type approved (or type accepted, not sure).


2008-01-08 11:51 pm
There are a lot of these available off-the-shelf for sending your MP3 player or WHY to your car radio.

Far be it from me to discourage anybody from building a transmitter, but the cost is trivial from e.g. DealExtreme: Cool Gadgets at the Right Price - Site-Wide Free Shipping - DX, you could just bust it open, they come with LCD frequency displays and remotes in some cases.

You may have a hundred watt linear amplifier available, but be aware that putting out anything more than a very small amount of power (50 nanowatts in the EU) is strictly illegal in just about every jurisdiction worldwide.

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