This circuit is based on a Siemens S566B integrated circuit. The circuit is from a Radio Electronics Experimenter and also has a digital control input.
This General Electric circuit is from the 80's. The PUTs used in this meter are not common...
This circuit provides a power of the order of 2 W, characterized by high performance. The output...
The sensor can be made using two bare wire or two screen with a piece of tisse between them. One...