Parts:C1 See Notes
R1 See Notes
D1 1N914 Diode
U1 4011 CMOS NAND Gate IC
K1 6V Relay
S1 Normally Open Push Button Switch
MISC Board, Wire, Socket For U1
- To calculate the time delay, use the equation R1 * C1 * 0.85=T, where R1 is the value of R1 in Ohms, C1 is the value of C1 in uF, and T is the time delay in seconds.
- S1 may be replaced with an NPN transistor so the circuit can be triggered by a computer, other circuits, etc.
- Most any 6V relay will work for K1. If you use a large relay, you my need to add a transistor to the output of the circuit in order to drive the larger load.