We found this solid-state relay circuit that can function as a shield in a Radio Electronics magazine from December 1989. The optocoupler is a phototransistor type.
The presented circuit is suggested by Texas Instruments (www.ti.com) in its Application Report...
This circuit with an industrial standard 4-20 mA interface uses a KPZ20G pressure sensor but can...
This circuit takes advantage of the inductance of the coil of a high-impedance phone to form the...