The Portsdown Digital Amateur Television transmitter has been designed by a team of British Amateur TV Club (BATC) members and has been promoted by the BATC to provide an easy, low-cost entry to home-built digital TV transmission.
The basic unit uses a Raspberry Pi, a Raspberry Pi camera, a local oscillator and a filter-modulator board to produce 10 mW of digital ATV on 146, 437 or 1255 MHz. All these items except the filter-modulator board are readily available from internet suppliers. The filter-modulator board can either be home-constructed or purchased ready-made and tested from the BATC.
Supported enhancements to the transmitter include a touchscreen to allow easy control, a video capture device to allow the use of analogue video cameras, a sound input USB dongle, multiple switched RF and PTT outputs, and an RTL-SDR dongle to add a basic receive capability.
Full construction details are on this Wiki https://wiki.batc.tv/The_Portsdown_Transmitter and the software is here with full build instructions https://github.com/BritishAmateurTelevisionClub/rpidatv. There is an active discussion forum here http://batc.org.uk/forum/viewforum.php?f=103
Even if you don't build the complete project you may find the composite video capture and streaming capabilities useful
Dave
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