This circuit was obtained from an American 1980s documentation. The frequency depends on the crystal and the circuit may be a PNP that reaches the generated frequency.
The AM QAM stereo system works experimentally with some stations, but it should not be equipped, as the...
This circuit was obtained from the October 1977 Radio Electronics magazine. The meter is analog, and...
This 3, 5, 6, 9 and 12 V power supply selected by a switch has a digital indicator of the selected...