This circuit was found in an old documentation, being able to generate signals of frequencies in the range of 50 to 100 MHz. The components are of the time.
Varicap or varactor is the basic component used in this circuit of an American 80's documentation. The...
This circuit was obtained from the October 1977 Radio Electronics magazine. The meter is analog, and...
This circuit doesn't use CMOS functions, but instead a bipolar transistor. The main feature for...