This circuit indicates a digital value through a moving bar. The circuit is TTL and must be powered by 5 V. We find this circuit in a Texas Instruments optoelectronics manual.
This configuration (using a logic gate with TTL compatible output) uses an amplifier transistor to obtain...
In addition to the didactic purpose, the figure circuit can also be automated. In this case, the...
The maximum time interval of this circuit depends on C1. Larger values can be used to get closer to...