This TTL circuit generates a 100 MHz signal for digital instruments. The CI is not easy to obtain, being of the high speed MECL type. The circuit is from a 1972 Motorola manual.
This is the basic configuration of a monostable TTL with the 74121. The trip is done with an NC...
This fixed source configuration with 78xx series regulators has already been explored in several...
In the figure we have a TTL logic interfacing circuit as CMOS logic using a 6N139 optocoupler...