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 very simple amplifier was found in the Philips Databook of 1990. The circuit is suitable for...
This simple circuit makes it possible to test visual fatigue by the ability to detect higher...
Found in the May 1988 issue of Radio Electronics magazine, this circuit is sensitive to small...