Stroboslave
Photograph Flash Slave for high voltage trigger flash units
like the wonderful Stroboflash.
Here is a 21st century technology -- ultra sensitive slave --
you can easily build and use with your Stroboflash units. It far
exceeds the capabilities of the vintage vacuum tube slaves and
even some new "peanut" slaves. I
designed this slave to light buildings out of doors at night.
For all you spelunkers that tool around in caves for jollies it
would work great there too. In
testing I was able to trigger the slave from over 400 feet away
using 1/4 power. As long as the phototransistor can "see" the
flash or a reflection of the flash it will trigger. Normal room
lighting does not affect it either. I suspect it will trigger at much further
distances but I ran in to a fence and could go no further. This
slave will not work with digital cameras that fire a pre-flash
prior to the main flash. I use this with a Nikon D70 digital
camera set to (M) manual mode.
Stroboslave does not work out of doors in sunlight. It is
intended for indoor or night time use only. Bright fluorescent
lights are OK.
>*<
Stroboflash Al
Finished unit:

I stuck a piece of foam weather stripping to the back of the PC
board for insulation and then used a rubber band to attach the
battery.
This pulse detected by the infrared sensitive phototransistor
is amplified by the 2N2222 transistor. This amplified pulse
triggers the gate of a 400v sensitive gate Triac. The Triac acts
as a switch triggering the Stroboflash head that it is plugged
in to.
Schematic:

Printed circuit board artwork:
PDF Artwork
Bottom on left, Top on right reversed for laser printing to
PC board.

Parts List:
Parts are available from Mouser Electronics
www.mouser.com
| Phototransistor |
OPTEK #OP598B |
| Triac |
LittelFuse L6004L3 or any 400v sensitive gate triac. |
| Any 2N2222 transistor |
|
| Resistors are 1/8 watt 10% values are
not real critical +- 10% is OK |
|
|