This circuit was found in an 80's General Electric documentation. The circuit uses uncommon components today like the PUT. Unijunction admits equivalent.
In this circuit, D.A. which is actually O. A. of an operational amplifier, which can be any type...
A narrow range of frequencies around 1 kHz is rejected by the high Q filter shown in the figure,...
This circuit, which uses a planar silicon sensor, is from a 1964 Electronic Design. The component...