Found in a 1964 Electronic Design this circuit compares two signals by providing the inverse of the algebraic sum of their frequencies. The circuit can be made with modern equivalent transistors.
This circuit was found in documentation from the 1980s. The transistor depends on the desired...
We found this circuit in a 1985 technical publication. The circuit uses PUTs to drive lamps....
This type of circuit, found in American documentation from the 1980s, triggers producing output...