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#164128 05/25/07 06:37 PM
Joined: May 2007
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Can anyone provide me info or a good website that explains in detail how a flash and Burst chokes work?

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Joined: Oct 2004
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What the heck is a flash and burst choke anyway? Never heard of it.

OTOH, what I think of is what was/is known as a "blowout coil", which was used on some old switches to extinguish the contact arcs.

Enquiring minds want to know... smile

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I'm baffled as well. A quick search turned up this lighting website -- http://www.flashtechnology.com -- which inludes "Choke, burst" and "Choke, flash" in its list of spare parts.

It seems to include things such as aircraft warning beacons, so I wonder if it's a reference to chokes used in specific applications such as strobe driver circuitry?

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Yes, Flash Technology is one of many companys that use Burst & Flash Chokes in their Beacon sysytems. The Beacon systems consist of many capacitors, relays, High & low voltage Transformers, Circuit boards and these chokes.I was unable to find any information to these chokes on their site or any other web site to give a better understanding of their use in the system. My guess is that they control the capacitors somehow limiting the output of the capacitor.

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Pauluk is correct in their use in Flash Technology's Beacon system. The system is used in Navigation and the strobes are used on towers to warn aircraft and as a mark for watercraft if close enough to water. Our work site has a stack with such lighting system and the system consists of these chokes but flashes site does not give details on how they work and i cannot find any other site that does. I was hoping some one out there could help.

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There are different ways that the specific control circuitry could be arranged, but you might like to browse through some of these links (scroll down a little from the top of the strobe section) for some ideas:

http://www.epanorama.net/links/lights.html#strobe

Here's one specific link which gives an outline of how capacitors and chokes can be employed in flash/strobe circuitry:

http://utopia.cord.org/cm/leot/course04_mod04/mod04_04.htm

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thanks pauluk for the reading material.

Joined: Nov 2005
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I haven't worked at a TV station since '91. I believe that our strobe controller had two modes of normal operation: Bright flash for daylight and a series or "burst" of less blinding pulses at night. The burst will give you more time for a fix at night and the bright flash is better for spotting a tower in the summer haze. I remember that our controller used CMOS logic but none of the details from the one time that I fixed it. Thinking back, the neighbors were complaining that it was waking them at night because it wasn't switching modes. Strobes, in general, require the use of a trigger coil.
Joe

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Thanks Joe for your reply. Our stack lighting has day and night modes, we too had many complaints from surrounding home owners with the strobes at night being stuck in day mode and this is one of the reasons i was able to get involved with them. Do you know how the flash and burst chokes work in the system? and how does the trigger coil work?
Thanks.

Joined: Nov 2005
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A trigger coil generates a HV pulse which causes the Xenon Gas to ionize to allow the strobing. I D/L'd one of their Flash head manuals. The flash and burst coils will taylor the discharge rate. Note that they don't show an iron core on the flash but do on the burst coil. The burst coil also has series resistance downstream. Less resistance and inductance will yield a very high current, rapid capacitor discharge and bright flash. The high inductance of the iron core burst coil and series resistor(s) will yield a lower current, longer discharge. Plus, you dissipate some of the power in the series resistance.
Joe

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