This circuit is from a Radio Electronics from October 1963. The transistor is a power transistor of the time, and two transformers are used. The input has 10k impedance and is powered by 12 V.
This circuit for link or alarm was found in the Encyclopedia of Electronic Circuits Volume 5 of...
This 9-pixel circuit has been implemented with 9 LDRs and can be coupled to a processing system for...
The purpose of the diode in this oscillator circuit is to limit the amplitude of the output...