This timer, like the previous circuits, uses a currently uncommon integrated circuit. The time is given by capacitor C1 and R2 which has the range of values indicated in the diagram.
The circuit shown is from the 1994 Linear Applications Handbook from National Semiconductor. Other...
This circuit was found in a 1997 magazine. It uses a CMOS 4060 circuit powered by 12 V which is...
This 1000: 1 voltage-controlled filter circuit was found in an Electronics Today International in a 1980s...