Johnathan Corgan writes: > Seth David Schoen wrote: > > >Someone proposed this a while ago, but Fabrice Bellard (who is also > >responsible for cool stuff like the tcc compiler, which lets you use > >C as a scripting language and lets the Linux kernel compile itself > >at boot time) has used a VGA card's DAC as an RF modulator to produce > >a valid DVB-T signal. > > I sure wish I could remember where to find it, but I've seen > demonstrated a program that would generate valid AM waveforms by > displaying certain pictures on a video screen. You'd enter a target > frequency (I think in the HF range) and choose a MIDI sound file, and it > would "modulate" the CRT display to emit RFI at that frequency with the > tones riding as AM modulation. Very spooky. It was a demonstration of > the security hazards associated with CRT displays (TEMPEST stuff) in a > very palpable way.
Probably Tempest for Eliza: http://www.erikyyy.de/tempest/ There's yet another similar project that I would like to track down that was using a VGA card. Does anyone here know if the VGA cards prevent you from controlling the DAC durinng the blanking intervals? Are the blanking intervals implemented in hardware or in software? -- Seth David Schoen <[EMAIL PROTECTED]> | Very frankly, I am opposed to people http://www.loyalty.org/~schoen/ | being programmed by others. http://vitanuova.loyalty.org/ | -- Fred Rogers (1928-2003), | 464 U.S. 417, 445 (1984) _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
