This circuit was found in a Popular Electronics from the 90s. The circuit uses common components today. The waveform of the generated signal is shown next to the diagram.
We found this circuit in a technical documentation from the 70s. It can be implemented with more...
We found this shield circuit in a 1991 technical documentation. The phototransistor can be...
This circuit was obtained from a Radio Electronics from October 1963. The 4 transistors must be...