The purpose of this circuit, which we found in an August 1973 Radio Electronics issue, is to determine the characteristics of a tunnel diode.
This circuit transmits beeps to receivers tuned in a wide range of frequencies placed nearby. The...
After starting, this circuit turns off the relay in a time that depends on the 4020 pulse-count. This...
This simple circuit can use general purpose transistors and SCRs like the TIC106. The warning...