Released in 1976 for $169.95 by Fairchild Semiconductors, the Channel F was the first video game console that used interchangeable and programmable cartridges, predating Atari's VCS/2600 by approximately a year. Each cartridge had a number printed on them and ranged from 1 - 26.
Nowadays the cartridges go for about $10 some going up to $20. The system itself goes for $50 to as much as $200.
