This Wien bridge oscillator was found in Radio Electronics from the 90s. The circuit uses the 741 which is a current component. The circuit requires a symmetrical power source.
Found in a 90's EDN, this circuit generates signals in the frequency range given by the graph. The...
The figure shows a circuit that shows how to control an optodiac to trigger a triac from the...
This circuit, from an American documentation from 1975, can be assembled with modern transistors such as...