Wireless flash triggers and copal shutters

[Ivan J. Eberle]

The older version Yong Nuo RF 602 transmitter (delta shaped) that I've got for my Nikons has a standard PC connector input and works great. Unlike simple IR triggers or optical slaves, I find it works at quite a distance outdoors, and around corners, etc. One of the best sub-$50 gadgets I've ever bought. Allows me to trigger my Nikon SB800s with a Pentax 645N (even waking them up from sleep!).

I opened the TX up and went looking for a pad as a pick off point to wake up distant flashes from sleep for a long term remote camera set. Found it, put a jack on it, and it works great with a PIR detector. The receiver also has an optical isolator that functions with higher amperage than most, so it triggers camera motordrives as well as flashes. Too bad they changed the form factor to make them all transceivers nowadays.

I'd have willingly paid a couple of hundred bucks for the set at the time just for the wake-up feature alone. Nikon flash wake-up protocol seems to be a digitally encoded signal, one I couldn't suss out with a meter or oscilloscope.

[chuck94022]

I'd have willingly paid a couple of hundred bucks for the set at the time just for the wake-up feature alone. Nikon flash wake-up protocol seems to be a digitally encoded signal, one I couldn't suss out with a meter or oscilloscope.

Perhaps it is, but my SB600 can be awakened by my Nikon FM3a, which Nikon brags is a fully analog system internally (of course that doesn't mean it can't generate digital signals at the hotshoe, but seems like a lot of work for a simple function). I assumed the flash was just sensing 5V on one of the secondary pads, but I've not put voltmeter to pad to verify. Sounds like you did a lot more research than me (that would be zero for me...).

[chuck94022]

Ivan, just out of curiosity I just put a voltmeter on my FM3a hot shoe and on my F4 hot shoe. The upper right pad (as you look down on the hot shoe from the shooting position) goes to +1.59 V on the FM3a and to +1.69 V on the F4 when the flash should wake up (half press of the shutter). Since all I have is a voltmeter here, no oscilloscope, I can't go further than the above.

I would imagine the the more sophisticated cameras interpose more sophisticated signals over the same pads, but I have no idea what. I do know that obviously the engineers at Yongnuo did not get the latest D800 communication protocol right...