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toolbox
19-May-2011, 08:16
Hey guys,
I picked up one of these to use with my Crown Graphic (it was a dollar plus $14 shipping). I figured I could rig up a battery for it as I've done with other equipment...didn't realize at the time that it takes a 510V battery (!). Sooo...I don't really want to spend a bunch of money on a new battery (particularly when I don't even know if it works), so last night I was thinking about other ways to use it... Anyone ever do any kind of conversion on these? I thought about hooking up a Quantum style battery pack, but a better (read cheaper) solution might be to hack another old flash and hook it up to the tube. I've got probably a half dozen Vivitar 283s sitting around, and I think the guts would fit in the Graflex battery pack... It should be relatively easy I would think to wire up the Graflex tube to the Vivitar flash. Would need to find a way to sync it of course. It could just be left in manual mode and fired at full power, or maybe find a way to mount the auto sensor on the handle, although that would complicate things.

Anyone ever do anything like this?
Cheers,
Scott

Edit--can a mod move this to the gear forum? Forgot I was in cameras LOL. Thanks.

James E Galvin
19-May-2011, 08:41
Are you familiar with high voltage safety? There is a big capacitor in a flash that can hold a lethal charge for hours or days. Best to have a safety observer watching over your shoulder who knows CPR. If you don't know what you are doing, this project could kill you.

toolbox
19-May-2011, 09:35
Are you familiar with high voltage safety? There is a big capacitor in a flash that can hold a lethal charge for hours or days. Best to have a safety observer watching over your shoulder who knows CPR. If you don't know what you are doing, this project could kill you.

Thanks for the concern, but yes I'm aware of the danger. I've worked with caps far bigger than what you'd find in a hot shoe flash, so I'm not too concerned about it.

nolindan
19-May-2011, 10:42
Modern flashes work at 200-300V.

A variac and the transformer/diode/cap from an old Microwave will give you 500 volts with no problem. Rewire the diode so that it acts as a classical 1/2 wave rectifier, microwaves use it as part of a voltage doubler. 24 volts in will give you around 500 volts out.

http://www.youtube.com/watch?v=GtIrLYH2DMQ