We found this circuit in a 1967 American documentation. The diodes are general-purpose and the input frequency can be between 80 and 800 Hz.
Two inverters of a 4069B type CMOS integrated circuit form this oscillator which is characterized by having...
Raytheon's used operational amplifier is rare today, but the configuration can be adapted to use...
Found in a radio amateur magazine of the 1980s, this circuit uses components that can still be...