Using a 4046 PLL this circuit generates rectangular signals in three wavebands that depend on the capacitors used. The circuit is from a Radio Electronics from December 1989.
This power source, obtained in a 1973 publication, suggests the use of partially burned germanium...
This circuit was obtained from an Electronic Design from 1964. Transistors admit modern...
The circuit is from the 1994 National Semiconductor Linear Applications Handbook but can be...