We found this circuit in the 1990 Motorola Linear Databook. The circuit must use symmetric source and has 10times the voltage gain.
This was a very popular instrument in the workshops of the 60s and 70s. It was a "top of the line"...
This circuit for analog video signals was found in a Linear Technology integrated circuit manual. The...
We found this circuit with NO and NC (series and parallel) sensors in the April 1975 Radio...