This circuit, which can be used as a shield, was found in General Electric documentation from the 1980s. The coupler uses a photo-SCR. The circuit admits equivalent components.
This circuit can use NTCs from 200 to 680 ohms, just change P2. For 200 ohms use 330 ohms, for 250...
This circuit was found in an Electronic Design from the 90's. It makes use of components from the...
This circuit for a frequency of 40 kHz was found in an old Electronic Design. There were no...