Composite - To - Ttl Adaptor For Monochrome Monitors

62 Dce be 1988 CeOMPOSITE - TO - TTL ADAPTOR FOR MONOCHROME MONITORS Among the welcome side-effects of the current invasion of IBM PCs and compatibles are the drastic price cuts for high-resolution, 12 and 14 inch, TTL-compatible monochrome monitors. The circuit described here makes it possible to use such a display in conjunction with a computer that has a composite video output only. EE Many owners of popular home com- puters must at some time have been en- vious of IBM PC users, because these are in a position to look at text and graphics on a restive, high-resolution, non-glare monitor instead of on a (modified) TV set tuned to channel 36, and barely capable of displaying 80 characters per line. Until recently, how- ever, the cost of a TTL monitor was such that manufacturers of home computers in the lower price ranges did not even consider equipping these with a digital output. The inexpensive adaptor circuit described here should allow many owners of the first generation of h...