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Note: Since this article has been written there have been many advancements in wireless video technology. The electronics used in this article may be outdated and unavailable in the current market. This article remains on this site as a reference and record of the Wireless Video Project and should be cited accordingly.
When it comes to flying R/C Aircraft, nothing can be more exciting than getting real time video of your flight. With a live video link you are able to “board your aircraft“ and see what you can’t from behind your transmitter. For me it all started with a still camera installed in an old trainer plane I had. The still photos I took looked neat but it was hard to aim the camera from the ground. I wanted a system I could see from the ground and maybe even pilot my airplane like a military drone aircraft.
I started researching what systems were available and the range they offered. There were some projects that utilize a consumer grade security camera made by X-10 (X10.com ) that transmits on 2.4 gigahertz. This system did not appeal to me because the range was limited to 100 yards or so and the frequency used does not work well around obstructions. Although this was a limited range system, It’s a good match for helicopter use because helicopters can fly a tighter flight pattern unlike an airplane. This type of system does not need an Amateur Radio License to operate (as some units require a HAM operator license to operate) and can be put together for $150 - $200. There were some other systems that were complete unit including video camera and transmitter ($120) that transmits a color image on UHF frequencies but the output power was low and promised only 300 ft range max. (Available at plantraco.com)
I wanted a system that would easily transmit a picture a quarter to half mile away. I searched further and found a web site wirelessvideocameras.com that also had prepackaged units for R/C use. They have a few units that did not require a HAM License, but most of these did not have much range and the ones that had good range were expensive and required a license. All of the units featured were 2.4 GHz and were in my opinion were a bit too pricey for me. I decided to experiment with an 434 MHz ATV transmitter called the Videolynx 434 (available from Transmitvideo.com) and this unit is what got me fired up about airborne video. This transmitter worked pretty well but required shielding from the receiver and did not offer sound at the time. After a few months of testing if found I needed a better solution for overall performance.
Finally After looking around some more I found a Transmitter on the web that was reasonable in price, lightweight, and powerful enough for range. The AVX900T4 was my final choice for this project. This unit transmits on the efficient 900 MHz band and did not interfere with the 72 MHz remote control receiver. Unlike the popular 2.4 GHz Band, which has a lot of traffic and needs line of sight to work efficiently, the 900 MHz band is better suited for long range applications being a lower frequency.
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