Transmitting video on radio FM band

[Duke]

Hi everybody,

I was looking for a way to transmit video on a long range, 15-20km (10 miles) ; I need this for a UAV project, or model aircraft with a onboard Tv camera.
But I found only too expensive or too heavy materials.
When I saw this :

http://www.electronics-lab.com/projects/rf/001/index.html

I thought, maybe I can plug the video RCA from the onbard camera instead of a microphone, and use a simple FM receiver plug on my AV enter from my TV.

So there is my question : can I use this transmitter for a Tv camera ? is there enough bandwidth on the FM radio band ? do you know an other easy schematic, for video transmitting with enough power ?

Thanks you !  :D

PS : Sorry for misspellings, I am foreigner  :-[

[audioguru]

An FM receiver has a bandwidth of 150kHz.
Video needs a bandwidth of 2MHz to 50MHz.

Ordinary old TV used AM, not FM for its video.

[Duke]

Thank for your answer.
If I understood, I need an AM transmitter, working on a higher band (around 200MHz, TV band) and in this way I can use a conventionnal TV with his tuner to receive the signal.

But I have little knowledge in electronics, how I can modify the schematic for this use ?

[audioguru]

If I understood, I need an AM transmitter, working on a higher band (around 200MHz, TV band) and in this way I can use a conventionnal TV with his tuner to receive the signal.

But I have little knowledge in electronics, how I can modify the schematic for this use ?

I have little knowledge in mechanics. How can I modify my cheap bicycle to make it into a luxury car?

The very old Greek FM transmitter circuit is completely different to a modern TV video transmitter circuit.

[Duke]

Wow, the difference between a simple audio transmitter and a video transmitter is so large ?
Hum, maybe I have to find another solution for the onboard camera.

One last question : if I want to increase the frequency on the FM transmitter (more than 108mhz), I have to change only few components (adjustable capacitor, coils) or this is too complicated ?

Thanks again for your time  ;D

[audioguru]

The bandwidth of the FM transmitter is much too narrow for video.
A Video transmitter circuit is completely different.

[Hero999]

Yes you do have to find another solutaion for your video transmitter.

You're right, that you can alter the frequency of an FM transmitter by changing the value of the capacitor and inductor but when the frequency approaches the transistor's transition frequency you need a faster transistor.

[Duke]

Ok, thank you audioguru and Hero999 for your advises.
I found something, a TV transmitter kit (UHF) :
http://www.ermes.free.fr/kier134.pdf (the documentation probably doesn't exist in english, sorry).
Maybe I will try this and see if with a signal amplifier I can reach my expected range.

[blueroomelectronics]

Wouldn't 10-15kM be well out of range of the remote used to control the model aircraft?

[audioguru]

My cheap Chinese RC model airplane has a radio range farther than I can see. Adding a camera and TV transmitter will allow me to see where it is going when it is too far away.

For 10km to 15km range then just increase the output power of the transmitters.

[Duke]

I planed this too, give more power to the transmitter, or add a small amplifier.