This crystal oscillator is indicated for the calibration of IF steps of common radio receivers. The transistor admits equivalent as 2N2222 or BF494. The circuit is from an old American publication.
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...