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  1. #11

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    Quote Originally Posted by Colin D View Post
    Tom, what do you think it might be?
    From my experience in radio work and other similar electronics like tape recorders and the like, I've learned the behavior of caps of all types. The old paper ones up through the various oriental modern makes. Yours is the big electrolytic that you suspect. And electrolytics DO go bad at a higher rate than the little types. Still and all, there are too many other components in a flash that are more likely to be the fault than the big electrolytic. That's why I do not place it at the top of the list in troubleshooting. You're just suspecting it because it's the easiest thing to blame by reason of being the easiest part to locate. Most of the rest of the circuit board parts are proprietary and hence; not available.
    A dead electronic flash is dead. As a compulsive restorer of electronic gadgets, I do not give up without a fight to fix something. But flashes are in my category of "irreparable spent items". I've worked on them, but very little can be done. Or should be done.
    When you restore an antique radio, you can afford for it to give more trouble later on. A flash is like an airplane, in that not working is not an option, ever.

  2. #12

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    I'll disagree with Tom, just a bit. Those flashes are pretty simple: charge up a bunch of caps and trigger them through a flashtube. Not much complex circuitry there, and any parts that can handle the voltage/current should work as replacements. Get the voltage/capacitance and size of the bad cap, and you should be able to find a reasonable sub. Now, I would agree with him on an SB24 and up...Nikon makes pretty sure only they can work on their gear. But an older Vivitar or Sunpak flash would be worth a look (after discharging and while wearing safety glasses, of course)

    Now, as to whether electronic flashes are *economically* repairable...that's pretty much a guaranteed, "No!" :-)

    I'd take it apart and have a look. Worst case: you were going to throw it out anyhow. Best case: you might learn something by looking around inside, and may even repair it.

    Source: electrical engineer, have repaired both studio and on-camera flashes, and have built and tested my own trigger voltage reducer boards.
    Last edited by Peter Simpson; 04-30-2014 at 02:00 PM. Click to view previous post history.

  3. #13

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    Quote Originally Posted by Peter Simpson View Post
    ...

    Source: electrical engineer, have repaired both studio and on-camera flashes, and have built and tested my own trigger voltage reducer boards.
    That is a significant difference between you and many others. I'm not, so I don't.

  4. #14

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    After I posted last night on #11, I went to bed and started prioritizing my suspicions, but didn't want to get back up and turn the computer back on to post it. If a flash isn't charging, here is my order of suspect causes: dirty battery contacts, corroded battery wiring, dirty or bad switch(es), xformer, transistor or other semi-conductor, and at last--the big electrolytic. Since the full symptoms were not told to us, the flashtube itself could be bad. A bad electrolytic will show symptoms of not staying ready for very long, pulling the battery down. For it to be dead-shorted or totally open is almost unheard of. You could charge it up and pop it with a screwdriver, if you don't mind a big firecracker exploding in your face. Be careful working on flashes. They're very dangerous. I suppose it could even kill you. At the least, an accident will be something you'll never forget.

  5. #15

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    Quote Originally Posted by Tom1956 View Post
    After I posted last night on #11, I went to bed and started prioritizing my suspicions, but didn't want to get back up and turn the computer back on to post it. If a flash isn't charging, here is my order of suspect causes: dirty battery contacts, corroded battery wiring, dirty or bad switch(es), xformer, transistor or other semi-conductor, and at last--the big electrolytic. Since the full symptoms were not told to us, the flashtube itself could be bad. A bad electrolytic will show symptoms of not staying ready for very long, pulling the battery down. For it to be dead-shorted or totally open is almost unheard of. You could charge it up and pop it with a screwdriver, if you don't mind a big firecracker exploding in your face. Be careful working on flashes. They're very dangerous. I suppose it could even kill you. At the least, an accident will be something you'll never forget.
    Ok, some relevant info was missing so here it is.

    1/The flash unit was pointing to the roof overnight
    2/ Next morning straight after plugging a LED battery pack into the same power board as the flash was plugged into I notice a strong rotten smell, not a burnt smell though.
    3/ The flash was not powered up.
    4/ After looking for the source of the smell for a while I came to the flash, it had a clear oily residue on the outside of the ventilation holes at the bottom and the smell was definitely coming from it.
    5/ Unplugged the unit immediately.
    6/ Took the front off to check the modelling globe and flash globe, they look fine.
    7/ More oily residue inside the housing, it seemed to be splattered in small droplets on the inside front wall.

    One technician at a camera shop I visited tonight believes without seeing the unit that a capacitor and circuit board have blown .

    Does that help?

    Colin

  6. #16
    AgX
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    The only source for a fluid at such strobe would be a electrolytic capacitator.

    Why did you not contact Multiblitz?

  7. #17

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    As a electronics technician I have fixed a lot of stuff.....Its sounding like a cap issue.

    I had a older multiblitz 702 head blow a cap once. I managed to finding a replacement
    Inside a small strobe "porta flash" brand it had a cracked case and a swap was done

    I got broken strobe and a friend got some beer, I managed to fix the 702 head and I still have it and it works fine.

    A technicians junk box is always the first place you look.

    When working on flash units :- Just make sure you short out any other caps in the flash, I use a big 1k resistor about 10wats soldered to two Multimeter probes. Don't use a screwdriver as you may be looking for two flash caps instead of one.

    Johnkpap

  8. #18

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    Quote Originally Posted by AgX View Post
    The only source for a fluid at such strobe would be a electrolytic capacitator.

    Why did you not contact Multiblitz?
    I contacted their distributor in Australia, not sure Multiblitz have an office over here but I will check.

  9. #19

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    Quote Originally Posted by Johnkpap View Post
    As a electronics technician I have fixed a lot of stuff.....Its sounding like a cap issue.

    I had a older multiblitz 702 head blow a cap once. I managed to finding a replacement
    Inside a small strobe "porta flash" brand it had a cracked case and a swap was done

    I got broken strobe and a friend got some beer, I managed to fix the 702 head and I still have it and it works fine.

    A technicians junk box is always the first place you look.

    When working on flash units :- Just make sure you short out any other caps in the flash, I use a big 1k resistor about 10wats soldered to two Multimeter probes. Don't use a screwdriver as you may be looking for two flash caps instead of one.

    Johnkpap
    Maybe all is not lost then. My only issue is that I have to find a friendly electrical technician in Melbourne who will first of all confirm the problem then see if it can be repaired. Do you know of anyone in the caper in Melbourne by chance?

    Colin

  10. #20

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    Now that we know the poop, sounds like the big electrolytic to me too. But the circuit board is obviously fried to have caused the problem. The flash is finished.

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