This circuit can be used with receivers to attenuate signals that may cause interference. The circuit is a 70s documentation for amateurs.
The Schmitt optical trigger current in the dark is low. The transistors can be the BC548 and the...
This circuit was obtained in an English publication of 1975. It is a circuit that stabilizes an...
We found this circuit in a publication for radio amateurs in 1974. The bipolar transistors can be...