Found in a 1980s American documentation, this crystal-controlled oscillator generates 100 MHz signals. The crystal used is 20 MHz. Modern equivalent transistors can be used.
This small audio amplifier is based on the LM390 with a minimum of external components. We found it...
The integrated circuit used is not common today. The circuit presents a bass boost according to...
This circuit provides two outputs of the same signal. One with the original phase and the other...