Based on an integrated circuit of the time, this circuit appeared in the October 1979 issue of Radio Electronics magazine. The circuit monitors voltages in the range of 10.5 to 16.0 V.
Using components from the era, this 90's EDN circuit is used in analog to digital conversion...
Found in an American publication from the 90s, this circuit allows the supply of 3, 6 and 9 V...
We found this circuit in an old Popular Electronics. The circuit is experimental, driving an LED...