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 current of this charger is determined by Rs. The circuit is from the 1982 SGS linear...
This circuit is used to connect an additional capacitor to a tuned circuit of a VFO. The circuit...
This alarm does not interrupt its operation when the power is cut. A battery is kept at a constant...