Suggested by Raytheon in 1967 documentation this circuit uses a lightbulb and LDR optical coupler of the time. The transistor determines the maximum current.
Found in documentation from the 1980s, this amplifier uses an integrated circuit from the time....
This is a one-channel application for the Texas Instruments TMP390 sensor obtained directly from...
This moisture-activated relay was obtained from an American documentation from the 1980s,...