This circuit was found in American documentation from the 1980s. The integrated circuit used is a voltage comparator of the time. Modern equivalents can be tested.
This circuit is from a 1967 US publication. The configuration can serve as a basis for designs...
The phasor is the ray weapon that we see in many science-fiction films. The characteristic sound can be...
This linear oscillator was found in a 1968 publication. The operational amplifier is from that...