This input circuit for meters, which can also be used as a shield, is intended for operation with very low frequency signals. The power supply must be symmetrical.
Found in a 90s Popular Electronics, this sensor operates by infrared reflection. The components are...
This circuit, which can act as a shield, was found in a 1990 PE Hobbyst Handbook. The circuit...
This circuit was found in an old American manual. It is intended for testing SCRs and thermistors using...