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12-22-2011, 06:36 PM   #1
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Kr vs. older flash units

According to the Kr Operating Manual, page 180, "Flashes with reverse polarity (center contact on the hot shoe is minus) cannot be used do to risk of damaging the camera and flash."

I have two older flash units (Vivitar models 252 and 2800) that would be OK because they both have positive voltage on the center contact. But they also each measure in excess of 180 volts on the center contacts. I suspect that the Kr uses a solid state switch and 180 volts surely would blow that circuit ( I wonder why the Operating Manual does not warn about this).

Although the electrical circuitry would be quite simple, the major challenge with a home brew-device would be machining the mechanical interface for the hot shoe from scratch (Unfortunately, I don't have a junker flash lying around that I could salvage the hot shoe from).

My question then is this: Although I could design and build a buffer using a low voltage relay and a battery, I wonder whether there is something like this available commercially? In other words, an attachment that isolates the high voltage of older flash units from what I presume is low voltage circuitry in the Kr.

12-22-2011, 06:50 PM - 1 Like   #2

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Do a search for "Wein Safe-Sync". It works. The problem is that the $50 price tag is difficult to swallow when there are plenty of usable flash units available for less or approx. same, e.g. Pentax AF280T, Sunpak 444D, 422D, 36DX, 30DX, Metz 40MZ-1/1i/2/3i, Metz 32Z, Vivitar 3500, 3700, 5200, 5600, ...
12-22-2011, 08:22 PM   #3
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Original Poster
The problem is that the $50 price tag is difficult to swallow when there are plenty of usable flash units available for less
That answered my question completely. I'm going see what's available in AF280Ts. Thanks for your prompt and informative reply to my question.
12-22-2011, 09:45 PM   #4
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For the $50 price tag you could also get some remote triggers, which would make the flashes a lot more flexible. Cactus V5 can handle quiet high voltages.

12-22-2011, 10:28 PM   #5
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QuoteOriginally posted by Opahujo Quote
I wonder why the Operating Manual does not warn about this
Because it says that you can only use Pentax flashes and all of those are safe
12-22-2011, 11:44 PM   #6
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Check Amazon for them. I picked up mine a while back there for $20 and it works fine. It's legit. I don't know if they still have them for that but it's worth a shot.
12-22-2011, 11:49 PM   #7
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For about $35 you can get a single Cactus V unit and it will do the trick. Set it to transmitter and insert it to the camera hot shoe. It has its own isolated hot shoe at the top where you can attach any high voltage (I beleive up to 400v) flash. Or with $60 you can get two of them and give yourself off camera flash options.

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