One Chip Video Test Generator

[ppppenguin]

I remember the Ferranti ZNA134 and ZNA234 chips. For 625 the xtal frequency was a realtively standard 2.5MHz. There were also the Philips SPG chips; the SAA1043 which really needed a bit more than 5V to work properly and the later SAA1101. I've played with all of these over the years, including designing the SAA1043 into a broadcast grade SPG.

I've not played with PIC, Arduino or Raspberry Pi etc but I reckon you could make a pretty good job of a simple pattern generator with a PIC and a few resistors. The resistors would be arranged as a R-2R DAC. The Domino 625 to 405 converter used a couple of PICs as its main timing logic.