FM Radio Modified to Transmitt

[unix60959]

Hey guys, A while back I followed a youtube tutorial on how to convert/make and FM radio transmitt on the FM band. So, I tried it out and it worked, but why does it work? shouldn't someting like this be impossible?

I've attached a video demonstrating the tranmitter:



If anyone has any ideas or info on why this works please let me know. Also are there any ways the transmittion could be strengthened ie. an antenna?

-unix60959

[G4LNA]

It's quite possible, all superhet radios have an oscillator that runs above or below the Inter Frequency (IF) amplifier, in the case of an FM radio it is usually 10.7MHz so at VHF that is not that far remove from the frequency that you want to listen to. All you have to do is to listen on another FM radio and you can hear the local oscillator on the other, then just modulate the one you are transmitting from and listen on the other. Yes, stick an antenna on it, about 4 feet long, it's surprising how far a few milliwatts travel.

[unix60959]

Thanks a lot for the information it was really helpful! I'll have to experiment with antennas