This two-port configuration of the 4001 was found in the April 1988 issue of Radio Electronics magazine. The timings are given by R1 and C1 as a function of the desired behavior of the circuit.
March 2017 - The new ERB-RD, ERB-RE and ERB-RG fuses from Panasonic's Micro Chip Fuses can now be...
Constant currents from 10 mA to 1 A can supply the load, depending on the selection made by S1. Q1...
The optocoupler in the figure uses common transistors and a phototransistor to drive a sensitive relay...