Fabrice Bellard has proven the concept of a low-cost DVB-T emitter based on a standard PC running Linux. Bellard's demonstration exploits harmonics generated by VGA video cards to pipe a usable VHF-range signal directly into DVB-T set-top boxes. Bellard says he plans to release the source code, given enough interest.

According to Bellard, the technology could form the basis of low-cost DVB-T emitters useful for testing DVB-T set-top boxes, cell phones, and interactive DVB-T/DVB-H applications. Alternatively, students could use the technology to develop and test DVB-T/DVB-H modulator software, Bellard says.

Bellard's emitter requires a PC running X Windows, a hacked VGA cable that connects directly to the RF input port on DVB-T receivers, and a video card such as an ATI Radeon 9200SE that supports 4096×2048 resolution at 8 bit color depth. Additionally, the video card must support having its pixel clock set to exactly 76.5 MHz, a speed that produces a secondary harmonic corresponding almost exactly to VHS channel 5, Bellard claims, adding that a simple analog frequency translator could improve signal quality and increase frequency range.

Bellard's demo includes a still MPEG of famous Swedish Playboy model Lenna

Bellard's proof-of-concept demo includes complete instructions for setting up a normal PC to display simple test images on a DVB-T set-top box. He also says he has written a DVB-T/DVB-H modulator that works with a hacked version of FFMPEG to display more sophisticated video signals, such as the image of legendary Swedish playmate Lenna above.

Additional details are available on Bellard's Website.

(Thanks to Alan Carvalho de Assis, for calling this to our attention.)

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