Again...back to war! types od iniciating mechanism of IED's are based on ambient ( temperature, somke/gas, sound, IR rays, proximity, humidity, x rays, or light) and commands made by car remote, cordless bell, fm radio, command wire or areo modelling. Now there's a very important features I want to share, command by intervals (with cameras )

The basic premise of the circuit is to use the 555 timer to output high at regular intervals (10s, 30s, etc.), activating a transistor which serves as a switch closing the “shutter” portion of the voltage divider and triggering the shutter on the GF1.

The 555 is being used in astable mode, which will generate a square wave with regular intervals. There are independent time spans for the output being high and low, and using a diode across R2 allows the delay between high signals to be longer than the length of the high signal itself (i.e. a duty cycle of less than 50%). I set the interval between shots to be about 15s, and the trigger itself lasts about 1s (to make sure that the camera fires, and I put it in single-shot mode to prevent duplicates). The values that gave me those times are a 22µF capacitor (C1), 10kΩ for R1 and 1MΩ for R2. You can adjust the interval between shots with R2, and it’s linear.

https://brandonevans.ca/post/text/building-an-intervalometer-for-the-panasonic-gf1/