This simple digital circuit tester can work with TTL technology when powered by 5 V and with CMOS when powered by voltages from 3 to 15 V. The circuit provides LED indications and uses current ICs.
This circuit is from a 1968 Electronic Design. The characteristics of the output transformer are not...
We found this circuit in the July 1988 Radio Electronics magazine. The frequencies are given by...
This circuit is from 1967 General Electric documentation. It uses SUS which are not very common...