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Thread: Building a universal flashbulb gun

  1. #11
    Steve Smith's Avatar
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    Building a universal flashbulb gun

    Connect the items in the sequence: battery, resistor, capacitor, flash bulb then back to the other end of the battery.
    No current flows until a bulb is pushed into its holder. The resistor limits the current so that the bulb doesn't fire when you push it in but it allows the capacitor to charge to the same voltage as the battery in a few seconds.
    The contacts in the camera connect to the junction of the resistor and capacitor and the junction of the bulb and the battery. When the contacts close the capacitor is connected directly to the flashbulb and can discharge all of its stored energy into the bulb in order to fire it.


    Steve.

  2. #12
    Randy Moe's Avatar
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    Dec 2011
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    Re: Building a universal flashbulb gun

    I love the Tilt-A -Mite and it's father the Foto-Mite.

    I buy them NOS and had only one with a DOA capacitor.

    The Tilt is ingenious design, as the 3 way bulb holder is amazing in it's simplicity, with push button eject of spent bulbs.

    Both Tilt and Foto have test buttons that assure you will get a 'flash'.

    Don't 'Hot-Wire' them with AC power, the Foto can be modified in many ways, big inside and has 2 HH connections.

    I buy the modern exact replacement battery, which is a bunch of button batteries stacked up. Or buy a box of 100 buttons and make your own. The battery costs more than a NOS Tilt-A-Mite.

    I never used these back in the day, but some say the BC flash holder is good for 100's of flashes before battery failure. I don't know, but mine are ready after storage for 6 months.

    I compared my Einstein to one P25 bulb and found them equal in fstop at same distance in my studio with actual testing. http://www.paulcbuff.com/e640.php Go to comparison data.

    I shoot all FB at 1/25.

    Do some searching here, there is lots more about flash and bulbs.
    Last edited by Randy Moe; 4-Jan-2016 at 13:34. Reason: Data

  3. #13
    Jim Jones's Avatar
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    Aug 2006
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    Re: Building a universal flashbulb gun

    Quote Originally Posted by Sylvester Graham View Post
    . . . Is it possible to look up the trigger voltages for flashbulbs of various types, dial in my power supply, connect the red probe to the lower bulb contact, and the black probe to the screw contact, and pop away? Either by turning on the PSU, or using alligator clips to connect the positive wire to trigger the bulb? . . .
    The old one-shot flashbulbs can be triggered by two or three flashlight batteries. That's what most flash guns used. AA batteries usually sufficed in the smaller flashes. Some charged up a capacitor with a small 15V or 22V battery, but this degree of sophistication isn't necessary.

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