hr(bob) wrote in message
...
On Apr 28, 2:09 pm, "N_Cook" wrote:
James Sweet wrote in message

news:EkoRj.9384$E77.9069@trnddc05...







"N_Cook" wrote in message
...
James Sweet wrote in message
news:ArnRj.637$PY5.15@trnddc01...

What seems strange is this transformer must be half or third of the
volume
of the ones in compact camera flashes but the tube is perhaps 100x
the
volume of the tube in one of those cameras (1cm diameter, 20cm
long).
Don't
know the joules rating of this one, a large studio flash unit, but
530V
standing voltage. Perhaps 2m of wire wrapped around the flash tube,
as
trigger, all in all seems inadequtely tiny in comparison.

I think I'll try 2 camera ones in series with 100 ohms initially to
try
and
localise why not triggering. I may try subbing this tiny stepup
transformer
with one 3 times the size from a compact camera, as am wondering if
it
could
be internally arcing actoss turns.

The size is virtually irrelevant, as Sam says, almost no current is
required. I've used a tiny trigger transformer salvaged from a
disposable
camera to trigger a huge (about 8" long) 1KJ flash tube. Some are
bigger,
some are smaller, it has more to do with age, manufacturing process,
and
the
need for compactness.

Is it possible to have a non-functional tube with no signs of problems
,
like the black patches on the ends of a fluourescent tube that is on
the
way
out.

This one looks perfect other than the glass is a bit dirty on the
outside,
because the distributed trigger stops any cleaning. Not been dropped,
no
cracked glass, no odd looking deposits on the elctrodes or on the
inside
of
the glass.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

Yes, it's possible, but not terribly likely. You should be able to test
it
by applying voltage to the tube and using a piezo flame igniter to
trigger
it.

I like that suggestion, just connect the arc pin of a piezo gaslighter to
the trigger wire, when the standing voltage is across the tube- pure,
minimilist test.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list
onhttp://home.graffiti.net/diverse:graffiti.net/- Hide quoted text -

- Show quoted text -

Let us inow what you find.


How do you test for lack of air in a xenon tube?
Putting a neon bulb and dropper over the trigger transformer gave plenty of
strike even in room lighting.
I've an old reserve piezo gas lighter that the metal grounding barrel on the
end falls off, ideal for testing this tube, but no flash over.
Trying to find a medium size xenon tube I have somewhere or will try with a
couple of copmpact camera xenon tubes or one removed from a xenon burglar
alarm flasher, both with some sort of droppers, later today

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/