4 Stage 555 Timer for Video Cam Control

4 Stage 555 Timer for Video Cam Control schematics

SW1-LED and R14 are an optional test indicator for setting up the cam.

C5,6,7 and 8 are 555 stability capacitors to prevent false triggering due to power supply spikes.

Power supply bypass capacitors are not shown. Place 330μF to 1000uF caps across power rails between timing section of circuit and relay / solenoid section. Place o.1uF caps across all IC power pins as close as possible to the IC's.

To minimize power consumption - use large value "R"s for R2, 4, 6 and 8. Up to 1Megohm. Circuit consumes approx