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 circuit allows 220 / 240V shavers to be used in the 110V network. The diodes can be general...
Found in July 1975, Radio Electronics magazine this circuit can use any operating circuit,...
Here we have in the figure the configuration of the circuit as a conventional Darlington. In this...