This circuit covers the bands from 1.8 to 150 MHz, with plug-in coils whose characteristics are given next to the diagram. The FET can be a BF245. We found it in old documentation.
With a touch of the push button the lamp is switched on. A new touch and the lamp go out, in this...
This circuit was obtained from Maxim documentation. The circuit has 4.5 and 5.5V thresholds for...
This circuit has a configuration very explored in our projects. The range can exceed 200 meters and...