We found this circuit in the August 1990 issue of Radio Electronics magazine. The two-digit circuit uses a pressure sensor and is powered by a 9V battery.
The presented circuit uses an optocoupler to trigger a triac. We found it in a Popular Electronics from...
This circuit turns on incandescent lamps (do not use any other type) when it gets dark. The...
This circuit shows how to use the TTL IC 7790 to divide a square TTL signal by 7. Duty cycle is...