Amateur TV, 70cm video systems.
While researching video systems for a recent project, I stumbled across something I had completely forgotten about Amateur TV systems.
Amateur TV is limited to those who hold a Technician Class or higher amateur radio license. If you don't have a license yet, I highly recommend getting one. ATV comes in several different frequencies; 70cm (420-450 MHz), 33cm (902-928 MHz), 23cm (1240-1300 MHz), and 13cm (2390-2450 MHz). This gives you a wide range of frequencies to choose from to avoid RF interference.
I used the 434 ATV transmitter from www.hamtv.com, which runs about 99$. This can be received on any TV that can receive analog cable signals via channel 59. My receiving system consisted of a 5-element Yagi antenna tuned to 434Mhz connected to an old VCR outputting to a small LCD monitor (the older VCR had better reception than a newer hybrid TV). I tried to use a USB TV Tuner at first, but I could not get a signal unless the transmitter was very close (they have very weak pre-amplifiers) and there was a buffering delay of about 2-3 seconds. Not good for FPV.
My range for the 100mW system ended up to be approximately 2500 feet. Next time I will get the 5 Watt version for another $100 that will give me much more range and will allow me to drop the VCR from the setup and just use a cheap portable LCD TV. Maybe if I am really ambitious, I will even pump the power to 20 watts with an amp.
Overall I was pleased with the system I had slapped together on a tight budget. The transmitter module was easy to use and, thanks to the circuitry being potted, even survived a 70 mph crash into the desert floor.
Feel free to ask any questions or share about anything ATV related. If it pertains to autopilot, airframes, and whatnot, just use the appropriate forum sections. If you use the audio channel for telemetry or vertical sync injection, that would be fine here since it is pretty specific to video.
I am getting some good stuff here as well. I honestly didn't think there were as many people here as there are who use ATV.
Is there an HD version of this?
WR8ATV in Ohio is pretty much the furthest along on that front. Check out this for planning a station.