Found in a 1924 documentation, this circuit is powered by 3 batteries, two of which are high voltage. The output is a high impedance headphone jack.
The figure shows the basic circuit of a relaxation oscillator with operational amplifier. The...
This circuit was obtained from American documentation from 1966. It triggers when the two input...
Found in an American 1980s documentation, this circuit generates high-intensity pulses for a...