Found in a 1968 Motorola publication, this circuit generates a high-powered audio tone when triggered. Equivalent transistors can be used.
We found this oscillator that operates on the third overtone in a 1975 amateur radio...
This timer circuit whose blinking time is determined by ambient light was found in the February 1970...
This circuit was found in Motorola documentation from 1968. The transistors are from the company,...