The circuit shown in the figure can be designed with more modern operational amplifiers, as it is from 1994 documentation by National Semiconductor. The power supply must be symmetrical.
With this name, we find a photorelay in a publication from 1966. The transistor is made of...
This 6-transistor Japanese radio from the 1960s used germanium transistors and had an output power...
The waveform generated by this circuit produces a sound similar to that of a bird. The circuit is based...