The purpose of this circuit is to reduce the ripple of a power supply. The circuit is from a Radio Electronics from March 1985. The transistor must have a capacitance according to the source.
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...