How to test for flash triggering?

Discussion in 'Camera Building, Repairs & Modification' started by Gerry M, Feb 21, 2011.

  1. Gerry M

    Gerry M Member

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    On a Minox 35 GT with Minox TC 35 flash. The flash works properly when test button is pressed. New batts installed. The camera body works properly w/o flash. Does the body complete the circuit to fire the flash? How do you test for this? The only other camera body I have with a hot shoe is an OM2n and the Minox flash wouldn't fire on it either, but I don't have another flash unit to compare it with. Any help would be appreciated.
    Thanks,
    Gerry
     
  2. Rick A

    Rick A Subscriber

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    Try shorting across the terminals on the flash. A short length of wire should suffice. A word of caution, only strip a short bit of insulation on each end of the wire, and leave the insulation on the middle to hold onto to avoid shock.
     
  3. benjiboy

    benjiboy Subscriber

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    I have the same camera and flash, just put the flash in the hot shoe and fire the shutter. If the flash fires with the test button it should fire on the camera. :smile:
     
  4. Gerry M

    Gerry M Member

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    Rick,
    OK, I tried shorting across the flash contacts and the flash fired. So, the problem must lie in the body?
     
  5. Gerry M

    Gerry M Member

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    I have tried that a number of times. No Joy!
     
  6. Rick A

    Rick A Subscriber

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    Is there a flash synch speed? Try cleaning the contacts on the camera and retest.
     
  7. Bob-D659

    Bob-D659 Member

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    Make sure the side contact on the flash foot is actually touching the shoe on the camera. Sometimes they get bent or jammed into the flash body and don't make contact.
     
  8. wiltw

    wiltw Subscriber

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    Given the fact that the flash fails to fire on both the OM-2 and the Minox, and the fact that you can short the contacts on the flash's hot foot to fire the flash, I blame the hotfoot for not contacting the camera's shoe contacts properly.
     
  9. benjiboy

    benjiboy Subscriber

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    There's no flash sync speed to set the camera sets it when the flash is on it all, the O.P can do is clean the flash contacts on the camera shoe and the flash, if it still won't work there's a fault in the flash triggering circuit of the camera.
     
  10. Gerry M

    Gerry M Member

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    After more poking around, it looks like the side contacts on the foot of the flash may not be protruding far enough to make good contact with the hot shoe. The contacts appear to be stuck in a bit. The flash did fire on the body once, so I am hopeful. I don't see any way to access these contacts. I hesitant to try any electrical spray to free them. I appreciate all input. If anyone has ideas of freeing these, please give a shout.
     
  11. Bob-D659

    Bob-D659 Member

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    Maybe you can bend the end of a pin to make a hook, reach in and pull sideways on the contact. I doubt electrical contact cleaner spray is going to help much.

    Usually you have to remove the foot from the flash to easily get at the contact workings. Easy on some flashes, almost impossible on others.
     
  12. Gerry M

    Gerry M Member

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    OK, time to throw in the towel. I managed to free up the contacts on the flash foot, so that the are making contact with the hot shoe. It does fire once or twice, but that's it. Odd tho that it will fire without problem by using the test button.I started to disassemble the flash housing and decided to halt there. For me, it would take a service manual to go further. It seems kind of pointless as I will probably never use the flash. Like I said in the original post, it just irritates me that it doesn't work.
    Thanks to all who pitched in with help.
    Gerry