Found in a 1964 Electronic Design, this circuit generates pulses based on an avalanche diode of the time. The circuit can be tested with modern equivalent components.
The sound produced by this circuit, from a 1978 publication, depends on the humidity between the...
In a September 1992 Radio Electronics article, we found this basic 555 circuit used to generate fixed...
This circuit is suggested by Motorola, using a 4N26 type coupler and an MC1733 type operational....