We found this circuit in an English publication from the 1980s. The circuit uses current components and can be tuned for frequencies between 300 and 1500 Hz.
Found in a 1969 documentation, this circuit consists of a multi-oscillator with neon lamps....
This high-performance circuit was found in the 1982 SGS Linear Integrated Circuits Manual. The...
We have in the diagram another way to make the null adjustment of an operational amplifier. In...