FM Transmiter

Hi to all. I want to ask if is it possible to create an FM transmiter that transmits 100MHz freq precisely and only 100Mhz. Thank you.

Welcome to ETO.
How precise do you mean? A frequency with an error of 1% would be easy, an error of 0.01% more difficult, etc. However, since 100MHz is in the FM band your transmitter would be illegal in many jurisdictions.

An accurate frequency is made with a quartz crystal oscillator and the transmitter uses one of its harmonics.

If it was precisely 100mc then it wouldnt be Fm.

dr pepper said:

If it was precisely 100mc then it wouldnt be Fm.

Click to expand...

Good point.
If an FM radio tuned it in then it would have no FM modulation and would produce only silence.

Audioguru's idea in post #3 is probably the most direct method. You might do well to read this article and use a 20 MHz, 25 MHz, or 33.3333 MHz crystal in the oscillator. Of course all of the tuned circuits would have to be adjusted for the crystal frequency and transmit frequency.

**broken link removed**8505023.pdf

By the way, even though if modulated the frequency would not be purely and precisely 100 MHz, it would on average be precisely 100 MHz -does that count?

(Edited to add link to pdf file)