This circuit with an unusual configuration was found in the January 1974 issue of Radio Electronics magazine. The frequency is given by L1/C1, and the transistors admit equivalents.
This circuit with JFET was obtained in a book on FETs of 1989. The circuit is still current since...
This circuit was obtained from National Semiconductor documentation from the 1990s. The circuit has a...
Found in 90s documentation from Analog Devices, this circuit employs operational amplifiers of the time....