Using a common crystal diode and a 741, this circuit can be used to detect microwaves. The circuit is from old documentation and the switch selects the gains.
The purpose of this circuit is to improve the reception of signals from the short-wave band. The...
This highly sensitive light sensor was found in a 1970 General Electric documentation. The circuit...
This circuit was found in a Popular Electronics from the 90's. The CMOS integrated circuit used is...