This circuit was found in Radio Electronics from the 90s. The components used are common, and the transistors and CIs must be equipped with heat sinks.
This Rytron transmitter was published in a 1953 book. The circuit can be implemented with a BC558...
Foto-Darlington for applications such as light sensor. In normal applications only the collector and...
This circuit was found in a 90s Popular Electronics. It generates tones given by the oscillators and...