We found this circuit in a Radio Electronics magazine from June 1992. The circuit has a power stage and is used with 4.5 MHz video TV signals.
In the figure we show a timer, this simple one with only one of the four gates of integrated...
This circuit is a sensor for photodiodes that can be used in optical couplers, encoders and other...
This crystal tester was found on a 90s Ham Radio. Transistors are commonly used. The circuit is for...