We found this circuit in the November 1975 issue of Radio Electronics magazine. It uses a digital module from the time with several adjustments. The power supply must have the indicated voltage.
Frequencies up to just over 100 kHz can be obtained with an oscillator based on one of the four...
This circuit, found in a Popular Electronics from 1992, is based on an oscillator and a crystal...
This is a discrete equivalent version of an open collector TTL gate. What we have is an inverter...