Shox Dr
Chief Engineer to Carlos Fandango
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Engineer1964
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wow Plug it in and see how quick the meter dials spin 
mind you don't look at the light, This is what happens if you do
mind you don't look at the light, This is what happens if you do
gavuk
artful-bodger
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Shox Dr
Chief Engineer to Carlos Fandango
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- East Yorkshire
Don;t you just love t'web. It looks to be a bulb for a Centurion Tank 98-1520
The 2kW Xenon lamp illustrated here was designed by Eric Beeson of the AEI Lamp & Lighting Company specifically to suit the low voltage and instant-light requirements of the Ministry of Defence for a new tank mounted searchlight.Prior to its development, the carbon arc had been the light source of preference in such applications - its very compact source working well with a large reflector to deliver a highly collimated beam of light. Incandescent lamps were popular for the smaller units, but they shared a common drawback with the carbon arc - their relatively low efficiency and hence phenomenal electricity consumption.
Mercury lamps had also been investigated for such applications, but their long-run up time posed problems for military service. British Siemens did come up with a rather intriguing design that was used for a short while though - a compact source mercury arc tube concealed within a magnetically-operated shutter all in a large outer bulb. The lamp was kept simmering at a low current, and when full light output was required the current was increased, the response in luminous flux being immediate and the increased arc current resulting in a magnetic field which opened the shutter.
The xenon lamp pictured here had to be specially modified for use on the 24V DC battery circuit employed in the Centurion tank. The third auxiliary electrode was connected to a small Tesla transformer, which allowed the arc to be instantly ignited while only the standard low operating voltage was applied across the main electrodes. In common with AEI and Thorn's other Xenon lamps, the end seals are of a very intricate design employing multiple annular molybdenum foils.
The 2kW Xenon lamp illustrated here was designed by Eric Beeson of the AEI Lamp & Lighting Company specifically to suit the low voltage and instant-light requirements of the Ministry of Defence for a new tank mounted searchlight.Prior to its development, the carbon arc had been the light source of preference in such applications - its very compact source working well with a large reflector to deliver a highly collimated beam of light. Incandescent lamps were popular for the smaller units, but they shared a common drawback with the carbon arc - their relatively low efficiency and hence phenomenal electricity consumption.
Mercury lamps had also been investigated for such applications, but their long-run up time posed problems for military service. British Siemens did come up with a rather intriguing design that was used for a short while though - a compact source mercury arc tube concealed within a magnetically-operated shutter all in a large outer bulb. The lamp was kept simmering at a low current, and when full light output was required the current was increased, the response in luminous flux being immediate and the increased arc current resulting in a magnetic field which opened the shutter.
The xenon lamp pictured here had to be specially modified for use on the 24V DC battery circuit employed in the Centurion tank. The third auxiliary electrode was connected to a small Tesla transformer, which allowed the arc to be instantly ignited while only the standard low operating voltage was applied across the main electrodes. In common with AEI and Thorn's other Xenon lamps, the end seals are of a very intricate design employing multiple annular molybdenum foils.
Engineer1964
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Now that is amazing, Can you not mount it on a wooden Plinth?? Not everyone can lay claim to one of those bulbs 
Seano
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Here's LMB's facebook profile pic!
That's either a very severe farmers tan.....
or GROSS STUPIDITY on every level...
Highway_Star
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Early xenons often had the third electrode for ignition, they don't now. Various chemical dopes are applied to the electrodes, as well as far better ignitors than in the early days.
A far more common use of thee lamps is cinema projection, they've been around commercially since the 50's but didn't see mass adoption until the 70's here in the UK. They are brighter, more efficient, cleaner and burn longer (lamp life is typically 2000 hours) than the carbon arc lamps they replaced. This had a more profound effect on cinema projection, and projectionists. It allowed the introduction of long playing devices (the entire film could be shown on one single projector, as opposed to two or more being 'changed over' every 20 minutes. This meant less projectors needed, real automation systems could be introduced and a massive reduction in projectionists and therefore operating costs for cinemas.
Xenon lamps are still in use today, the light source in the current digital projectors is xenon arc.
Same type of lamp is used in video projectors, follow spots and those amazingly bright and focussed car headlights.
Expensive lamps though, a 2kW cinema lamp will set you back around £500, DC supply must be super smooth <7% ripple, typically we aim for <3%, needs a lot of ventilation and they are a bit risky when handling. A glass bulb full of pressurised gas goes with a bit of a pop! But treat it with the respect it deserves and there is no problem.
Some of the big ones have water cooling, these are quite rare, in the 15kW region, Only really used in Imax cinema, skytracker floodlights and the like.
A far more common use of thee lamps is cinema projection, they've been around commercially since the 50's but didn't see mass adoption until the 70's here in the UK. They are brighter, more efficient, cleaner and burn longer (lamp life is typically 2000 hours) than the carbon arc lamps they replaced. This had a more profound effect on cinema projection, and projectionists. It allowed the introduction of long playing devices (the entire film could be shown on one single projector, as opposed to two or more being 'changed over' every 20 minutes. This meant less projectors needed, real automation systems could be introduced and a massive reduction in projectionists and therefore operating costs for cinemas.
Xenon lamps are still in use today, the light source in the current digital projectors is xenon arc.
Same type of lamp is used in video projectors, follow spots and those amazingly bright and focussed car headlights.
Expensive lamps though, a 2kW cinema lamp will set you back around £500, DC supply must be super smooth <7% ripple, typically we aim for <3%, needs a lot of ventilation and they are a bit risky when handling. A glass bulb full of pressurised gas goes with a bit of a pop! But treat it with the respect it deserves and there is no problem.
Some of the big ones have water cooling, these are quite rare, in the 15kW region, Only really used in Imax cinema, skytracker floodlights and the like.
Highway_Star
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You won't get it lit on car batteries!
The open circuit voltage before ignition needs to be around 100v for that lamp at a guess. You also need to kick it with about 40,000 volts, usually from a spark gap oscillator (effectively it's a RF spark transmitter). At the moment of ignition the power supply needs to trade volts for amps, dropping to around 24v@75A.
The open circuit voltage before ignition needs to be around 100v for that lamp at a guess. You also need to kick it with about 40,000 volts, usually from a spark gap oscillator (effectively it's a RF spark transmitter). At the moment of ignition the power supply needs to trade volts for amps, dropping to around 24v@75A.
Highway_Star
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Hitch, you're maybe not far off the mark.
I have a TIG box, which you feed DC in and it provides HF and gas control.
Now, the DC I use comes from a cinema xenon arc lamp supply, 'cos I got 2 of 'em doing nothing else, and they are controllable from a pot (which I'm slowly building into a foot pedal).
Anyhoo, I've had the lid off the TIG box, the HF start circuit is very similar to the xenon arc ignitor. Spark gap, capacitors and HF transformer.....
Xenon PSU is constant current, so I reckon you could light and run this off a welder...
The light is really not good for you, it's full of nasty UV and IR, will cause skin and retinal burning in seconds.
I have a TIG box, which you feed DC in and it provides HF and gas control.
Now, the DC I use comes from a cinema xenon arc lamp supply, 'cos I got 2 of 'em doing nothing else, and they are controllable from a pot (which I'm slowly building into a foot pedal).
Anyhoo, I've had the lid off the TIG box, the HF start circuit is very similar to the xenon arc ignitor. Spark gap, capacitors and HF transformer.....
Xenon PSU is constant current, so I reckon you could light and run this off a welder...
The light is really not good for you, it's full of nasty UV and IR, will cause skin and retinal burning in seconds.
Wedg1e
They call me Mr. Bodge-angles
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I have a 50-gallon oil drum full of old x-ray tubes, if anyone wants to replicate this...?
