I've been doing a bunch of reading about digital ATV operations lately. I was originally motivated by hearing about the HamTV project aboard the ISS. Back in 2007, I got re-energized into ham radio by learning that for the 50th anniversary of Sputnik, the amateur satellite AO-51 would broadcast a cool message that I heard with a simple HT. I'm wondering if I'm having that kind of a moment now: the idea of creating a station to broadcast digital television seems challenging but doable.
While reading up on the necessary bits for a HamTV downlink station, I found that this little satellite receiver which sells for less than twenty-five dollars could be used to decode signals from the ISS. It receives DVB-S signals, which are used by direct satellite broadcasters like Dish Network. But in thinking about how to go forward with the project, it seemed to me like trying to aim directly for a satellite downlink station was likely to be a frustrating endeavor. It requires a number of different subsystem to work together, but trying to receive the DVB-S from the ISS (given an intermittent schedule) would be difficult to test together. So, I started looking for resources that I could use to build a similar terrestrial station, including both a transmitter and receiver.
A couple of cool links:
The DATV-Express board is a $300 exciter board that is in limited production. It seems very cool. Reading the Tech Talks on this site yielded a lot of good information, I'm particularly pondering the information in this one, about designing a digital TV station.
Another similar project, but available more as a board/kit is the Digilite project. An interesting variation of this project is the DigiliteZL project, which makes for a compact and interesting setup.
I also like the CQ-DATV magazine. It's got lots of cool information, published in a series of magazines available in a variety of e-book formats. They also have a broad collection of interesting articles on the Digilite project, which I'm currently reading over.
I'll probably stick to more experimentation with SSTV, but this stuff fascinates me, and I may have the opportunity to do something interesting with it in the future.