This circuit can be used to test crystals from 1 to 20 MHz and also has an output to measure their frequency. We found it in the November 1998 Electronics Now magazine.
This circuit is from a Radio Electronics from April 1972. The circuit uses power transistors of...
We found this simple circuit in a 1999 documentation. It converts low-intensity sinusoidal signals (a...
This very high voltage circuit was found in the 1990 special issue of Radio Electronics...