Using one unijunction transistor and two bipolar transistors, this circuit generates a signal from 25 Hz to 3 kHz. The circuit is from Electronics Now magazine, January 0, 1994.
This circuit warns when the headlight bulb is on. We found it in a Popular Electronics from the...
The oscillator shown in the figure keeps its frequency constant in an active cycle adjustment...
This circuit was found in an Argentine publication from the 1970s. The circuit can be assembled with...