This circuit is from American documentation from the 1980s. FETs support modern equivalents.
The circuit shown is from a 1975 Motorola thyristor manual. The triac can be of the TIC series and the...
This crystal tester was found on a 90s Ham Radio. Transistors are commonly used. The circuit is for...
This circuit was found in Radio Electronics magazine from April 1960. It was in an article that...
