Xenon Igniter: Sources?

[Jim Cassedy]

Last year the igniter in one of our 35/70 consoles went out. My very resourceful back-up
projectionguy, who had worked at the theater at some point years ago, knew we had a
used back-up stashed in another console. He managed to quickly install that one and
save a (70mm) show. But I don't think either of us know the whole history of that part,
and exactly where it came from or why it was originally removed.
While the replacement has been working, I don't fully trust it, and it takes several tries
to strike the lamp. We have a wholebuncha 70mm titles coming up this summer, and
it would be somewhat of a major 'disaster' if we couldn't strike one of the lamps.
In the past I've occasionally seen these pop up on e-bay but I haven't seen one in a
while, and I've been kicking myself for not buying one the last time I saw one listed.
I've entered the part number online, and some listings show up, but most of them turn
out to be old/expired or from electronics surplus dealers who have gone out of business.

So- - does anyone have any idea where I might be able to find one of these?
XenonIgniter.jpg
It's from a STRONG HIGHLIGHT II console. (I'd suggest going back to carbon
arcs to the boss, but carbons are also getting almost impossible to find)

> "PLAN B" I haven't tried opening this thing up yet. I'm wondering if there
might be any repairable parts inside. I'd imagine there are a some hi-voltage
diodes & one or more capacitors and perhaps a coil or two. Has anybody here
ever seen the inside of one, or done a repair? (A circuit diagram would be a
welcome find, too)

EDIT: Shortly after typing the above message, I found a U-Tube video which shows
the inside of a very similar igniter. It clearly shows the inside (which is about what I
expected it would look like) and there's even a hand-drawn circuit diagram. It's not
the same part number as the one I've got, but it's a starting point.

SCREENSHOT:
IgniterInside.jpg

U can C the complete video here:

https://youtu.be/6zb-PAuxegk?si=4l1MF0ILBRuFiivh

[Dave Macaulay]

I don't know how they work beyond sensing the lamp voltage and zapping when it's a lot higher than arc voltage. There are capacitors and a circuit board inside, and a potted coil of not a lot of turns of heavy wire. Those capacitors stay charged with a voltage that really gets your attention if touched, for a very long time. Be careful.

[Alan Lyman]

I think you can still get some from IREM in Italy. They are still in business

[Stefan Scholz]

Wasn't it, some of these DC/ single impulse igniters had a very simple circuit. More or less the starting circuit of a photo flash in cheap cameras of the past, a DIAC conducted, once the DC voltage reached 90 + x volts, thereby discharging a capacitor into the ignition coil of the "flash tube". In this case the 15 kV flash start is fed into the resonant circuit of he 1 to 5 Tesla transformer of the bulb circuit. So the pulse reached 50 to 100 kV, which safely ignited the Xenon bulb.
The burning voltage of a Xenon bulb, 20 to 40 V, is too low to trigger the circuit.
This was way cheaper to build, than the legacy igniters using a 115/220 to 15 kV transformer, captive sparc gap and Tesla resonant circuit.
Plus it provided way better RF interference values.
Therefore, if your genuine igniter is like the one you mentioned, finding thr fault is not too difficult to do.

[Jim Cassedy]

I think you can still get some from
IREM in Italy. They are still in business

I've always liked the IREM xenon & carbon arc rectifiers I've worked with.
They seemed to be well made, and in the few instances where I did have
a problem, they used mostly standard parts I usually could find at almost
any large electronic supply house.I'm glad to hear they are still in business!

(edited) some of these DC/ single impulse igniters had a
very simple circuit. More or less the starting circuit of a
photo flash in cheap cameras of the past,

That's exactly what I was thinking when I saw the circuit diagram in the
U-Tube video I posted a link to. It was also similar to cheap disco-type
strobe light I built from a science kit as a teenager many years ago.

[Tony Bandiera Jr]

Have to ask: Did you try the obvious and contact Strong or a Strong dealer to see if it might still be available? Or if they have a suitable later model replacement?

Those DC powered igniters sucked ass as Joe would say. I had lots of issues with them in my service days and more than once I ended up replacing them with a standard AC powered igniter. And before you ask I don't recall exactly how to wire up that retrofit. I do recall that I got the time delay board and regular igniter and traced out the appropriate wires in the console to get it to work. (It's now been over 35 years since I did that modification, and I don't have any saved paperwork.)

Edited to add: The main reason the DC igniters sucked ass is they relied heavily on the boost voltage from the rectifier being high enough and robust enough to drive the circuitry, then the high voltage transformer to get the lamp to strike. If the rectifier's filter caps were weak, the incoming line voltage too low, or the lamp was more stubborn than normal to strike, it'd fall on its face every time. The ones powered from the AC line didn't have those issues and would brute force the pulse every time without fail.

[Jim Cassedy]

Have to ask:
Did you try the obvious and contact Strong or a Strong
dealer to see if it might still be available? Or if they
have a suitable later model replacement?

No,Tony, that was too obvious! lol
I figured that would be just too easy, so I didn't give it a try. Another source
I haven't tried yet is INTERNATIONAL CINEMA in Miami and Atlanta (I think).
The have a lot of parts n'stuff that don't show up in their e-bay listing or their
website. But I have managed to get several obscure parts from them in the
past by e-mailing them my needs. They do charge top dollar for their
merchandise, and (in my opinion) their shipping and "handling charges" are
higher than many places, but that hasn't stopped me from using them, since
theyare a good company and they stand behind their merchandise, which
doesn't stop me from using them.

[Tj Hopland]

You could also try Strong Lighting. They took over the follow spot and search light side of things. I never worked on the later versions of the follow spots but it seems fairly likely that they used that same igniter at least in some version of the spot. I think they are still producing a xenon light so they may still be having that or a very similar igniter made.

One nice thing about the console is there is 'room for activities' so you are not tied to a very specific form factor and terminal location like you are in some of the lamphouse designs so something in a different package may be workable.

[Mark Gulbrandsen]

I would call Strong and see if they can supply you one. They still produce the Super Trooper Follow Spots, and they also have a ton of parts still in the warehouse. I know a tech that was able to get an igniter from them about a year ago. And yes, the bad one can certainly be repaired unless one of the potted in coils has failed.

[Josh Jones]

If push comes to shove, many of the series one machines used a stock Irem igniter with would be up to the task if you have the room.

[Tim Reed]

When I worked for Strong, the DC igniters were all potted. I never even saw a schematic. Repairs? Pshaw! Replace the whole thing. I can't see the drawing in the video very well - does anyone have a clearer version?

[Jim Cassedy]

I can't see the drawing in the video very well -
does anyone have a clearer version?

I couldn't see the diagram in the video very well either. So I had taken a
screenshot and played with the contrast a bit so that I could print it out.
The igniter in the video is a different model number than the one I've got,
but it looks physically identical to the one we removed from service. I'm
guessing there might be differences in the component values between
the two, but the actual circuit is probably the same. I've been too busy
to open the 'bad' igniter we have and try to do any actual troubleshooting.
My supervisor had promised to find a replacement, but so far that hasn't
happened. I reminded him of it again the other day. Even if I do get a new
one, it might be fun to troubleshoot and repair the old one in my spare
time. . if I ever manage to actually get any spare time.

Here's the circuit from the video. It's actually a very simple and clever design.
IgniterCircuit.jpg
Except for the final output transformer coil, which is 'potted' into the side of the
case, and trigger-coil and the spark-gap tube, the rest of the components can
be relatively easily so sourced and replaced.

[Tim Reed]

I couldn't see the diagram in the video very well either. So I had taken a
screenshot and played with the contrast a bit so that I could print it out.

Thanks, Jim! That's much better than mine.