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Multi-Trigger 2 Kit, unassembled

MT2 (discontinued)


The Multi-Trigger 2 has been discontinued. The Multi-Trigger 3 kit is available now.

Click images to enlargeMulti-Trigger 2 control box

Control box above; cables below

Microphone cable Variable-width photogate cable Interrupter photogate cable
Microphone Variable-width photogate Interrupter photogate

The Multi-Trigger 2 has the following features:

  • all components hard-wired for durability
  • on-off switch
  • operates on standard 9V battery
  • jack for optional 120-240 VAC to 9 VDC adapter
  • LEDs to indicate power on, photogate alignment, and event triggering
  • test button for the delay unit
  • inputs for microphone and both variable-width and interrupter photogate cables (parts for cable assemblies included)
  • switch to select for microphone or photogate input
  • sound trigger can be activated by a finger snap at a distance of 30 ft. or more
  • fine (up to 0.05 s) and coarse (up to 0.5 s) delay adjustments
  • switch to select one of two delay ranges (0 to 0.5 s or 0 to 0.05 s)
  • continously-variable timeout setting up to 1 s
  • sensitivity adjustments for the sound and photogate triggers
  • external input to connect other triggers to the delay unit
  • instant and delayed optically-isolated outputs for camera and flash

The PC board used by the Multi-Trigger 2 is shown to the right. Locations of components are labeled. Holes are numbered to aid in making connections to the lid of the control box.

PCB for MT2

The PC board is bolted to the lid of the project box. This reduces the possibility of breaking connections when the lid is removed to add or replace a battery.

PCB installed in Multi-Trigger 2
Either of the MT2's two optically-isolated outputs can be used for camera or flash. These outputs cannot be used for older model high-voltage (>80 V) flash units. However there is an optional extender kit that provides outputs for high-voltage flash units. Click here for the extender kit.


The Multi-Trigger 2 kit requires assembly. Experience in wiring, soldering, and troubleshooting electrical circuits is assumed. Here are the assembly instructions. (The current build is Build 3.)

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