Flash tube discharge circuit design

[cybose]

I am trying to build a flash triggering circuit, and was looking for
some information on Capacitor charging, specifically the part mentioned
at
http://www.repairfaq.org/sam/strbfaq.htm#strbuci

An image of the part is here-
http://www.repairfaq.org/sam/uc350vcp.jpg


Its extremely difficult to find an miniature inverter transformer that
can be bought off the shelf. Has anyone ever tried to do this?

V

 

[mike]

I am trying to build a flash triggering circuit, and was looking for
some information on Capacitor charging, specifically the part mentioned
at
http://www.repairfaq.org/sam/strbfaq.htm#strbuci

An image of the part is here-
http://www.repairfaq.org/sam/uc350vcp.jpg


Its extremely difficult to find an miniature inverter transformer that
can be bought off the shelf. Has anyone ever tried to do this?

V

Go down to your local Walgreens, or anywhere that develops
single use 35mm camera pix on site. They get 17.5 cents for every camera
they return to be refurbed. I had no trouble getting them to
sell me as many as I wanted for 20-cents each.
It will have everything you need.

Be very careful
taking it apart, 'cause the big cap is usually charged
to lethal voltage. Stated another way, you can die...
mike

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[OBones]

Go down to your local Walgreens, or anywhere that develops
single use 35mm camera pix on site. They get 17.5 cents for every camera
they return to be refurbed. I had no trouble getting them to
sell me as many as I wanted for 20-cents each.
It will have everything you need.

Same advice here. I even have the schematics for some of the most
popular ones if you want.

Be very careful
taking it apart, 'cause the big cap is usually charged
to lethal voltage. Stated another way, you can die...
mike

lethal voltage yes, but the charge is not that big. It will give you a
shock but will not kill you if you are in good health. I did take a few
"strikes" while poking around those things, it hurts, but I'm still
alive (I think).

 

[cybose]

The schematics would be a big help. The flash tube I have has a higher
W-s rating than the ones in disposable cameras.My thinking was, if I
can figure out what the 'miniature transformer' (don't know what else
to call it) does I can get one which would work better with the flash
tube I had...

 

[mike]

The schematics would be a big help. The flash tube I have has a higher
W-s rating than the ones in disposable cameras.My thinking was, if I
can figure out what the 'miniature transformer' (don't know what else
to call it) does I can get one which would work better with the flash
tube I had...

What's important is the voltage required. You can get as many
watt-seconds as you want by paralleling up caps. Just takes longer to
cycle.
mike

--
Wanted, Serial cable for Dell Axim X5 PDA.
Return address is VALID but some sites block emails
with links. Delete this sig when replying.
FS 500MHz Tek DSOscilloscope TDS540 Make Offer
Bunch of stuff For Sale and Wanted at the link below.
MAKE THE OBVIOUS CHANGES TO THE LINK
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[Al]

The schematics would be a big help. The flash tube I have has a higher
W-s rating than the ones in disposable cameras.My thinking was, if I
can figure out what the 'miniature transformer' (don't know what else
to call it) does I can get one which would work better with the flash
tube I had...

Are you talking about the trigger transformer or the step up transformer?

Al

 

[mike]

lethal voltage yes, but the charge is not that big. It will give you a
shock but will not kill you if you are in good health. I did take a few
"strikes" while poking around those things, it hurts, but I'm still
alive (I think).

The above response is IRRESPONSIBLE!!!!!
Just because you didn't die, doesn't mean that people should be casual
with a charged cap from a flash. You can die just as easily from the
head injury you get when the shock knocks you on your ass...except maybe
if it was protetected because you already had your head up your...

I've got an eye that doesn't work quite right. I accidentally grabbed
the second anode cap on a tv that had been off for days. When I flew
out the back of the set, my shirt caught on the antenna lead. It
flipped up and scraped across my cornea. The thing that hurts you ain't
always the primary stupidity.

mike

--
Wanted, Serial cable for Dell Axim X5 PDA.
Return address is VALID but some sites block emails
with links. Delete this sig when replying.
FS 500MHz Tek DSOscilloscope TDS540 Make Offer
Bunch of stuff For Sale and Wanted at the link below.
MAKE THE OBVIOUS CHANGES TO THE LINK
ht<removethis>tp://www.geocities.com/SiliconValley/Monitor/4710/

 

[cybose]

The step up transformer.
One of the not-so-cheap flash units had about 750V across its capacitor
after about 7 seconds, running off 6V DC. What kindoff transformer do
they use for the stepping up part ?

 

[Don Foreman]

I am trying to build a flash triggering circuit, and was looking for
some information on Capacitor charging, specifically the part mentioned
at
http://www.repairfaq.org/sam/strbfaq.htm#strbuci

An image of the part is here-
http://www.repairfaq.org/sam/uc350vcp.jpg


Its extremely difficult to find an miniature inverter transformer that
can be bought off the shelf. Has anyone ever tried to do this?

V

You'll find transformer design info and vendors at:
http://tinyurl.com/a4uvm

 

[Rich Grise]

The schematics would be a big help. The flash tube I have has a higher
W-s rating than the ones in disposable cameras.My thinking was, if I
can figure out what the 'miniature transformer' (don't know what else
to call it) does I can get one which would work better with the flash
tube I had...

Call it a "trigger transformer" and you'll probably get more
google hits.

Good Luck!
Rich

 

[cybose]

That was very helpful.