This circuit is suitable for use in radio receivers to improve the quality of weak signal stations. The circuit was suggested by the May 1994 issue of Electronics Now magazine.
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...