This circuit was obtained from HAM Radio magazine in an 80's issue. The FETs are types of the time and the frequency is determined by the crystal. The circuit operates at voltages from 3 to 9 V.
This circuit allows the detection of RF signals using the lowest range of direct currents of a...
The MC496 integrated circuit used in this application is not common today. Motorola's circuit...
This window comparator circuit was found in a Popular Electronics from the 90s. The circuit has a...