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.
Found in a 90’s Popular Electronics, this circuit applies to almost any operational amplifier. With...
This circuit is suitable for calibrating old oscilloscopes. It was found in a 1980s documentation. It...
We found this circuit in the April 1979 Radio Electronics magazine. Note the filter capacitor bank...