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.

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Wayne,

Timing is everything! I am studying for my Technician class now, I hope to take the test in late July, or sometime in August. I would echo your advice about obtaining a Ham license, to anyone interested in transmitting video from their aircraft, FPV or otherwise. The test should not be a challenge for anyone here. I would recommend the ARRL publication, "Ham Radio License Manual", available here form the ARRL web store. Be sure to get the 2nd edition, the question pool changed July 1, 2010 and is good through June 31, 2014. You can also download a copy of the question pool (good to 2014) here. The entire test is only 35 questions and a passing grade is 26. There isn't a code requirement any more, so nothing to be intimidated by. Many of the questions can probably be answered by most people here without any additional studying.

In short what are you waiting for ATV is the way to go!


Nathaniel (no call sign yet.....coming soon)
As N8TV, ham radio is the way to go.
Earl
Earl,

I was tired when you posted the above reply, at the time I was just happy with the support your reply offered.Now I get it N8TV! Funny LOL!

Nathaniel (aka N8!)
For folks in the US, the Ham bands are the way to go!

-- Mike (KB9RMK)
Hooray,, the HAM's are coming out of the woodwork AND talking HAM tv which is hard to get info on. I was thinking about the exact transmitter you mentioned. Thanks guys!

Tim
KCØYOL
N8TV is my REAL vanity call
Earl
Earl,

Leave it to me to over think a simple statement!

Nathaniel
I was into ATV for quite a while. Built 5 atv repeaters!
Earl
Excellent information and advice Wayne..an inexpensive optimal solution.

Is it legal to attach digital telemetry data into some of the horizontal scan lines?
If not....
Is there an equivalent ham setup that can handle long range telemetry in a similar way?
2M FM radio reaches a long way even without repeaters. Packet telemetry would send the data.
The near space ballown launches use very low power 2M packet for data. Up high, even a low power signal will go hundreds of miles depending on altitude.
Earl
Sure Mike, that's where they put the subtitle info & lots of other stuff. There's lots of unused scan lines in the vertical sync interval. You can buy obsolete broadcast quality vertical sync injectors cheap, cheap, cheap on eBay. As a matter of fact, the FPV'ers are way ahead in the cheap telemetry area by using the sound subcarrier that's already there on most of the TV transmitter modules. I haven't seen any of the AP groups take advantage of that technology yet.
Good call on the sound subcarrier. Sound is pretty worthless on a UAV unless you want to perch and do recon. Nothing annoys me quite so much as watching a You-tube vid and hearing BZZZZZZZZZZZZ of the motor. It's like our version of the vuvuzela.

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