This circuit was found in an ancient American documentation. With it is possible to double the frequency of a transmitter For the range of 6 meters obtaining 8 W. The circuit makes use of varicap.
The frequency of this circuit, that makes use of a tunnel diode as an active element, depends on...
This circuit uses a sensitive reed relay to control external loads. The time delay is given by the...
This circuit uses the 741 Operational Amplifier to drive two LEDs. The LEDs indicate the signal of...