This circuit uses a quadruple operational amplifier of the time. The circuit is from the 70s but can be implemented with modern operators that require the use of a symmetrical source.
This oscillator can generate signals from 100 kHz to more than 50 MHz depending on the crystal used...
Found in a 1980s American documentation, this circuit appears with variations elsewhere in this...
This circuit was obtained in a 1969 documentation. The circuit modulates both the emitter current and...