Remote Shutter Cable for FPV

[canad2006]

Gitup site refers to an FPV cable for remote shutter, which is not available yet, but could be built as DIY.
http://www.gitup.com/en/blog/22_Git2-Remote-Shutter-for-FPV.html

Did anyone try to build this? A video would be very helpful.

 

[Shawn Lewis]

Im attempting too, but lacking some details. As what is the "pulse" is it 5v for stated period of time, or is the time specified actually PWM which is contstant?