This circuit can be implemented with other comparators in the same series. The circuit is from a component manual and the supply voltage between 3 and 12 V depends on the application.
This sensor circuit from a 1967 Ferranti documentation uses components from the era. The circuit...
This is the receiver for the previous circuit transmitter. Similarly, no information about the...
Found in a 90s Popular Electronics, this circuit uses two PLL tone recognizers to trigger by touch an...