This circuit is from a documentation on the MC1539 from Motorola and may, however, be implemented with equivalent operations. The transistor also supports equivalent.
Only signals about 1 kHz can pass through this tuned circuit. The main component is a operational...
This capacitive sensor that operates with a high frequency oscillator was found in Radio...
This circuit was obtained in a 1973s documentation. The transistors may be BC558 for the PNP and...