The circuit presented is from the Motorola Linear Databook of 1990. The integrated circuit is a transconductance operating and the power supply need not be symmetrical.
Found in an Electronics World of 1966 this circuit is intended for use with a microphone as an...
This VFO (Variable Frequency Oscillator ) has the output frequency controlled by a potentiometer....
This simple alarm circuit was found in the May 1990 issue of Radio Electronics magazine. The...