Found in 90's Electronic Engineering this circuit can be used to measure phase angles between two signals from 0 to 180 degrees. The components used admit modern equivalents.
Found in Radio Electronics from the 90s, this circuit uses a 741 and can be changed to other...
With a light pulse on the Q1 sensor the circuit turns on and locks. To switch off, a light pulse...
This 10-minute timer was found in the July 1994 Radio Electronics magazine. The relay must be...