The World’s Most Powerful Single Searchlight Unit

[LightSward]

:thumbsup: I'm able to spin highly accurate reflectors after a few practice runs, but:
-- I need to be quieter in my shop; so for now my searchlight activities are now severely limited until I can find a new place. The drunk neighbor is bothered by sand paper sounds. I make too much noise for this area. I'm on notice...after living here twelve years, never had problems until this drunk moved in. Sigh. It's understandable the drunk who builds bonfires:thumbsdow in the condominium driveway wants to do so in quiet darkness...lol.

 

[LightSward]

Well, I have a few dollars to spruce this thing up for some public displays. I'll be adding a barrel and perhaps a lens system for rain protection. I' almost finished with the new base system, mainly for lowering the searchlight closer to the ground level to make transportation and handling easier and providing a more stable platform in case of strong winds.

The searchlight is getting a makeover, ready for some shows. Starting with a new base to help sturdy things.

The bottom of the searchlight will be three wheels and two stabilizing rods to keep the searchlight steady in most weather conditions. The four small upright wheels will support a rotating platform the searchlight will be attached to. The color will be perhaps this cranberry color that sold out already, and some white and blue pin striping.


Here is a quick look at tools and near completion of the new searchlight panning platform foundation. Should be a little more steady.

Tools out and ready. A little paint running on a few spots when I had to move platform when it started to drizzle.


I have some different washer and sleeve combinations I'll experiment with to get the smoothest and stabilize rotation of the searchlight itself if all this works out reasonably well.

3/4 inch bolt and a set of washers, rings, shafts and placement holders will help keep searchlight aligned during movement.


Should look good with this new platform and a barrel and subsequent raising of the light output efficiency as I'll be able to unmask more of the light bulb and make the beam about 15% brighter and slightly thinner with some alignment of the four reflector quarter panels.

 

[LightSward]

Making some progress.
I apologize, my once trusty photobuckets are giving crummy quality images and services. I am doing my best to salvage as much of this as I can.

Here you can see the turntable, with four tracking wheels underneath and large sleeve bearing in middle with large steel support brackets for lateral forces should hold the yoke steady.




A closer look at this turntable for the searchlight.

Close up of the steel lateral force brackets integrated with the sideways, forward and back forces common with searchlight manipulations. You can see the top of the 3/4 inch diameter bolt used as the inner section of a sleeved and back side washer bearing. I hope to have the searchlight mounted tomorrow and begin the construction of the "barrel". Light works awesomely, but have to make it look like what people expect to see...lol.

 

[LightSward]

Added those searchlight support arms and then mounted the searchlight again...Yeah..!

Assembling the basic searchlight components.

Just mounted the arms to the panning base platter...awaiting the searchlight to be installed using portable '"lifting crane".



Crane is great. I could not do so many things without this indispensable tool...like a big, silent, strong, helping hand.

This portable crane is a back saver. It's literally like having a super strong extra helping hand. Here I have the searchlight lifted and will simply slide it and the searchlight base together to install searchlight.



Different color ideas, leftover paint, finally decided on Cranberry red with blue and white "pin striping" to be added when cranberry red painting and searchlight component assembly is finished.

Searchlight installed. originally I was experimenting with different colors, yellow, blue, now "cranberry" red. I'll add Blue pin striping to balance the two main gang colors I may run into in Detroit...lol.


Nice frontal view showing what will be a better looking searchlight next few days as the "barrel" is added for light protection and a "finished look".

A yes...this will light the way to some positive changes ...coming to a city near you...lol.


Things will look much more professional in the next week or so while searchlight is prepared for "SHOWTIME"!

Here's a nice profile shot, showing some of the electronic start and control equipment.. The uneven searchlight rim was a result of experimenting with different finish parameters and different ideas of how I was going to connect the four quarter sections.
. > The "barrel" I'm about to build and install will even this out and give a more attractive look and make the searchlight look more like a "searchlight". Won't really change it's beam, although I will adjust the back reflector to allow more light onto the primary since the barrel will now protect people's eyes from the blinding raw light from the bulb.

At this point the searchlight is not being finished as a dissasemblable unit, but as a whole single unit. I would have manufactured it as a single unit and maybe cut int into four quarters but i had to make it this way because of severely limited space. My quiet neighborhood has become restless at all my noise. I can't wait to find another place, shop, business location or a whole new home where it will be quiet when I want it to be, but i can somehow make lots of noise at three in the morning when I feel like working on stuff...LOL..".:thinking::twothumbs:naughty:

 

[LightSward]

Here is a back up Tesla coil ignition device for the searchlight. This Tesla coil in of itself is a light show with over one foot or longer electric sparks.

This new, Tesla coil uses an old school design, producing anywhere from a quarter to half million volts of electricity at 250 MHZ frequency...sparks over a foot long. This one is built to last using mechanical spark gap and fan and neon transformer to power the primary coil with five 'tuned' windings. The new electronic Tesla coils have to have their solid state MOSFETs replaced often.! The other electronic and homemade Tesla coils were only about 75,000 to 150,000 volts, with less than six inch sparks.


Some of the following images show the stunning lightning display.

With out the lightning rod.


With a lightning rod but no hand wand...(even though you don't 'feel' these high frequency sparks at RF wavelengths, they can still be potentially harmful to nerves and blood vessels without feeling the damage.).

Here the Toroid has a lightning rod added to draw a more concentrated spark. Other methods are flat shaped Toroids, etc., and other properties of the current can be changed.:naughty:

A little over the top, but I wanted to be sure to ignite the searchlight during the show without ignitor issues. A light show for sure....(just have to keep anyone with a pace maker, insulin pump, etc, away along with computer stuff. My personal experience is there is an occasional glitch in any nearby computer or printer, so I isolate the lines as best I can and clear the area...out door use mainly, or large rooms...yeah sure). Many engineering or science based fraternities have these inside during parties but people can be potentially harmful to themselves when they party too much.:thinking: As I showed earlier, I have built a homemade one, but I can't completely rely on the lower voltage to ignite the bulb under the current conditions until I have more developmental money to throw at this.

 

[LightSward]

Working on the final "barrel design", and making adjustments to the searchlight bulb orientation and focus-ability.
Here are some really cool photos of my Tesla coil making lightening bolts a foot and a half long.

Just by having this nice big Tesla coil, i can be sure I'll be easily igniting my searchlight during this time I'm figuring out just how I'm going to get affordable ignitors for the production run of this searchlight.

I took some photos of the Tesla Coil in front of a Grand Canyon Painting I'm still finishing, now with electronic lightening. This is a light show of itself. Now I can feel confident I can ignite the searchlight.

Here the Toroid is open top with no lightening rod.
The Toroid, (the doughnut shaped metal object on top), can be changed in various ways, creating different type lightening. Adding miniature lighting rods creates the concentrated long bolts, where just the doughnut shaped toroid creates more random bolts like these.

Kind of hard to see it in bright light, but here's a photo anyway.

Hypnotic just watching the sparks. Feel like a little kid playing with a science fair project, that I actually like.



Voltage for budget people, can be measured in this range by measuring the length of the spark. Yes that is a small bolt of lightening traveling 12 to 14 inches up the side of the yard stick. As yardstick chars, the carbon ash conduct electricity much more easily. At high voltage, anything dark colored, tends to conduct electricity, even plastic.

As you probably already know, a low budget method of approximating voltage in the tens of thousand plus range is to measure the length of the spark...


Just having a little fun with the Tesla coil, before I wrap it up for the light show.

Didn't want to risk staying too close to the lightening to get a clear shot, ...bolts were making the camera take pictures at random when I approached too closely..

For my Video, see if this link works:
https://www.facebook.com/video.php?v=10203064552829881&set=vb.1087492680&type=2&theater

 

[LightSward]

Don't know if anyone has been paying attention to some of these neaw searchlight companies like NASA and a few others that make ridiculous Candle Power claims..?..! NASA Searchlights make some of the most outrageous claims that some of their lights make 2.8 Billion C.P. or more...!...all on 2,000 watts...! Total B.S. :toilet:

Both pictures of one of my older 1,200 watt lights to the right in both photos, with halogen 1,000 watt to left in first photo. Nice focused beam is a tank light with 2,000 watt Xenon to left in second photo, with an incandescent 1,000 watt bulb, another 1,200 watt HMI but with total parabolic reflector at only 7 inch diameter and then my 1,200 HMI with 'efficient' reflector.

The reason I bring this up is Lumen and Candlepower. Lumen being basically light output from source such as my 380,000 lumen 4kw HMI bulb I currently use, and Candle Power largely being how well collimated those lumen photons get aligned. Several companies claim their 250,000 lumen 2 kwt modified HMI produces 3 billion, (that's right 3 BILLION they claim), something for nothing. I realize my present reflector still needs work, but the beam is "efficient" and bright for the wattage, because the lumen output from the bulb is largely placed in the beam. Candle Power rating is high but could be much higher when perfected in due time. My gripe is NASA searchlight, among other things clams their searchlights which can be plugged into a regular wall outlet far outperform any of the old 60 inch GE or Sperry or 24 inch tank lights searchlights by a factor of 5 or more, yet their resulting beam isn't impressive at all. In fact they have to point the searchlight near horizon, and it's only as the beam passes directly overhead do you really even see it, unless it shines on nearby trees or buildings too. They have the larger one, (refurbished 60 inch lights, gutted with three of their lights instead), and it's dim. It uses, (as they show in video), hardly any power, thin wires etc. Wow, amazing how they get supposedly so much light out of a small amount of power, yet they claim new technology from the '60's with a small 30 percent increase in light but they parade it like it's way out of this world. Like I said, the results are ho hum for what they claim in Candle power.

My searchlight has been booked and ready to go to a big event in Detroit, planned for December 3rd, 2014. This event will be downtown between the river front and the GM and other high rises downtown.:twothumbs Investors have paid for an elaborate antenna system installed on top of these buildings to beam internet signals to the impoverished neighborhoods in Detroit. Half the people in Detroit don NOT have internet access at all, even cell phone coverage is spotty. :sick2: The signals beamed from the highrise buildings downtown will be a high speed internet link that will be transmitted to various "Safe Centers of Hope, eventually numbering in the hundreds, throughout the city. During the day and night, various 'gala' events are to be held, the best WAS going to be when the Mayor of Detroit turned on the light of hope, (instead of the ribbon cutting), he'd throw a switch and my searchlight would come on, along with many others I was bringing. He mentioned the competition. Politely reminded him on the physics of light beams shining in the night sky. The competition uses stretched figures, because according to them a pocket laser pointer is billions of candle power where as my big ole' searchlight is only one 250,000,000, (250 million), candle power. Yes my beam spreads a little faster than a laser, and if it was tighter I could claim up to 800,000,000, (800 million), like the WWII 60 inch lights, mine can still be seen for many more miles. Those ads are full on misleading lies.:candle: In a few days, I'll post some of their garbage so you can make up your minds.

What the heck happened. Well it was all arranged, reservations made and then the final meeting to discuss the show's details, an accountant with a lot of power, joins the multi person phone conversation, and after a while, in the middle of the meeting, just starts destroying my, long ago approved, budget for getting the searchlights out there to Detroit...I wasn't cheap, being an upstart business with prototypes in tow, heading into a snow storm, for many miles with more than a mere rental to own, but a whole production run, (strung along was I ..?),.... He starts acting like no one approved it, or that my prices are too high, etc, as if no one had approved this or anything. The accountant head honcho, tried to get me to drop a significant dollar figure in exchange for all the publicity I was to get as payment instead, (I was already expecting publicity, anyway...lol). Don't have the money to do that, I explained, otherwise I may have originally considered it while carefully constructing the road trip and shipping costs budget. Anyway, without going into detail, I was shocked, (not electrically...lol.), my this irate accountant who froze my contribution. Well good luck to them, because after seeing what they have available to them, and looking at the competition, they aren't going to see the searchlights they do rent from someone else, more than a few blocks. They won't be able to see them in Canada like they would have seen mine. I looked at the competition's beam shots and they just don't have the "punch" to compete with the city lights and be seen very far. Most of the competitors beam shots involve foggy conditions and the searchlights aimed low to the horizon and beam can only be seen passing directly over head or opposite, when hitting a building or nearby tree.

Now I'm in dept for extra work done on the searchlight in anticipation of going to Detroit and need to sell some items...such as the cool looking Tesla Coil I was going to use as an emergency back up bulb ignitor....basically brand new with only about five minutes testing use., for a mere $525. Hope for the best to them and already re-pitched them on my brighter light, for when they come to their senses and come crawling back to me. I'll be nice.:wave:

There, got that off my chest...damn accountants...okay my friend accountants, don't get too mad at me please. LOL.

 

[LightSward]

:sick2:...Just have to harp on this misleading Candle Power claim by these low wattage searchlights from NASA searchlights. I noticed many of their high candle power searchlights have such a low lumen count that their beams can only be seen if beam is shined directly overhead and near horizon in semi-foggy conditions.

Notice how small the wattage is for the slightly advanced HMI light, (same as I use).
[Some of these NASA searchlights aren't even bright enough to be seen more than a few blocks away, unless they aim the searchlight directly overhead near horizon and in foggy conditions. Notice these outrageous, almost never heard of Candle Power Claims. Total B.S. in effective crowd gathering ability. Just had to get that off my chest..]


Just to compare, a high candle power light compared to a low candle power but high lumen count searchlight that I made...as seen on other posts...just for comparison.

The brightest searchlight on the right side is one of my old homemade HMI 1,200 watt searchlights at maybe 80,000,000 candlepower compared to the Xenon, 2,000 watt, (estimated), 200,000,000 million candle power searchlight with a thinner, but slightly dimmer beam. Most individuals could only see my light on the right more than a mile away. Candle Power is good at describing beam shape and thinness, but not total brightness. with that said I'd like to acquire one of those tank lights in the future.:thinking:

 

[lucca brassi]

Results on this first real attempt for making a 24 inch reflector from sheet metal came out about what I predicted. Learned much...first of all use hard, stron wood or steel for mandrel...the soft particle board type ply I used disintegrated during shaping and caused a pitting to occur. Still I was impressed with the overall concept proving this test showed me. Now I just have to raise capital for real tooling...lol.

Looks nice and smooth, while spinning 800 RPM. The final finished product will be quite impressive.


Using primitive tools, I was able to cut this just about perfectly and centered it without much vibration during high speed operation. I used a foot pedal to control the lathe motor, (an inexpensive drill...very impressive how much power that thing delivered.)

Piece of flat 26 inch diameter sheet metal blank ready for being spun into a 24 inch reflector.

Not too pretty when viewed after slight disintegration form my shaping tools I made from Re-Bar pieces. I polished the ends into a "Cobra Head" shape, but I had to apply so much pressure, I accidentally cut and mangled the reflector at the end of the spinning. Still I learned so much from this. Now I just need another shop location,...my neighbors ran out of patience with me and now even just drilling a single small hole into some wood, just drives them crazy. Sigh.

Mandrel was made of not so strong particle board and liquid wood fixer upper, so it slightly disintegrated during the spinning, which caused all these little deformations in the metal. Surprisingly...Works well reflecting the light into a fairly tight beam..:shrug:

I did not see how did you bend metall sheet , but i think you could use wheel in way similar https://www.youtube.com/watch?v=FHvtieU4-7Y and https://www.youtube.com/watch?v=1EtApg0Hgyw

PS: Can you tell me why is a problem to use normal satellite dish antenna as parabola ?

 

[LightSward]

I did not see how did you bend metall sheet , but i think you could use wheel in way similar https://www.youtube.com/watch?v=FHvtieU4-7Y and https://www.youtube.com/watch?v=1EtApg0Hgyw

PS: Can you tell me why is a problem to use normal satellite dish antenna as parabola ?

The two videos are exactly how I'm attempting to do this, but I've had to stop all searchlight production until I can find an affordable shop location, (Attempting to finish the World's Biggest Searchlight, in secret, cosmetically and functionally). My condominium association told me to end ALL manufacturing processes in my garage, or face fines. I had poor results because I was just learning how to do this and did not have the proper tools...so as usual I made my own. I didn't have the strong wood type I really needed and I used a top coat layer to harden the "Dremel", so it disintegrated as the metal was shaped. I'm very hopeful to take this further, but now I'm broke, and no income source for now. Full Stop on all my searchlight activities. BUMMER.

Why I don't use satellite dishes is for several reasons. First of all; every-time I looked into using one, ...non available. The optical characteristics as far as focal length and total light output captured did not align with my requirements. If you look at most dishes, the feed horn, (focal point), is usually far enough in front of the dish, that a large amount of the light would be wasted. I have seen several dishes that came close to what I was after, but it was still very much in use, and many units I like, use the old screen mesh, which I would have to cover and build up to create a reflective surface.

If you find a dish that seems reasonable, it will probably work. You can try covering it with many different materials like fiberglass boat repair kits, build up with cement, platic, liquid wood, all kinds of possibilities. I think people could have good results with dishes. I just prefer to do things the hard way, (laugh), and make them from scratch myself. :naughty:

Good luck.

 

[lucca brassi]

no thanks , I'm more in dive lights waters ;-)) , but I would like to made tesla coil , like you to inspire students or visitors when visiting our laboratory

 

[LightSward]

no thanks , I'm more in dive lights waters ;-)) , but I would like to made tesla coil , like you to inspire students or visitors when visiting our laboratory

Let me know how I can help inspire visitors visiting your laboratory.

 

[LightSward]

Very unsettling, but many of my photos have vanished from this post. I will try to find out what is going on here. My photo buckets seem to be just fine.
I apologize, but one of my photo hosts has unreliable and unstable links, (Facebook based), and this caused a large amount of my photos to vanish over he last few days. Apologize, but with all the photos I posted I'm not able to update all them do to a variety reasons, mostly time.

 

[LightSward]

Well I've started a new Photo-bucket site. I hope that clears up all the vanishing photos and the low quality replacement photo-bucket site that used to work well.

Originally I built the World's Largest Searchlight, (otherwise known as the; "Lord of Lights"), for a light show scheduled and rescheduled multiple times, until I don't think Quicken Loans has much money now, so the show is probably off. I won't be able to completely finish the cosmetic properties or make this into the
beta version i was hoping for. This is mainly due to limitations on space and my lack of large enough vehicles to transport this beautiful masterpiece. I am going to semi-temporaily/permanently; mothball the large components and transfer the light bulb and support equipment to the 36 inch Gorilla. I'll be able to manage my shop space more effectively until I get a contract I can use to afford leasing factory space. Will be able to transport this smaller version of still a very bright light easily in my compact car. Will still be in the 380,000 lumen range ans compared to the WWII giant Sperry and GE 60 inch searchlights with 425,000 lumen output.

H:thumbsup:ere are some of the last photos you will see of this beauty for a while.

Nice profile view showing half completed cowling to reduce light glare. The light is fully functional, the additional work is for cosmetics and all weather operation. This is ready to be re-engineered for Beta and Gama production. See the next operating version in the 36 inch Gorilla.


View of the searchlight overseeing the quiet neighborhood.

Photo shows how big the light is. I didn't get all the sheet-metal complete, the exhaust ports and access panels installed. Light works as is, but I needed to still install a front lens to keep the rain out and fans for cooling.


Nice frontal view of the searchlight

Hopefully someone will be able to sweep me off my feet with a great offer to buy, lease, trade and or barter some kind of searchlight base, kit or assembly ability so I can make these out of "spun metal", in my much needed larger shop space.

 

[LightSward]

https://www.flickr.com/photos/11735136@N06/16091593017/

I'm not able to keep the quality of photos as high as I have, due to photobucket issues. My apologies.

 

[LightSward]

Well I'm getting the miniature version the modified Gorillaz searchlight almost ready I've got the generator so I should be ready to go to renting this thing for a while

 

[LightSward]

Just about ready to start testing out and nearing completion of the 4,000 watt upgrade to the Gorilla. Will use this to help open a new McDonald's near here, if I can get this finished real soon..!

This Gorilla conversion, is similar to the upgrade going on with the Nighthawk and it's 1,200 watt powerful HMI arc light-bulb., to make it all weather ready with it's new glass lens top and yoke system.

With the massive amount of heat produced by the 4,000 watt HMI bulb, I had to use three cooling fans with a forth passive forced exhaust vent mounted directly over the intense light-bulb, integrated with the split back reflector..! I've had to upgrade my, still home-made, ignition system directly into the fiberglass shell to make all the components weather resistant to allow searchlight operation in rain, sleet, light hail, snow with little or no winds, or fair to light winds with no precipitation, all possible to operate the searchlight in. I have to work on the ballast and generator being more weather resistant now... This is going to fit on the roof of my car now. Maybe I can transport the Monster with my near homemade roof rack that's better than the one I purchased.

Will upgrade to a better photo system soon.

Wish I hadn't lost all the photo locations...taking things a little longer to find and upgrade to a photo-bucket system that I can afford on a Bum Budget.

 

[LightSward]

Here is What the new World's Biggest Light looks like. All the components from the 72 inch light are now in the 36 inch Gorilla. The focal length isn't as big, so it's beam will be a little wider. The focusing is accomplished with a delta plate for three dimensional adjustments. I'll add vent hoods and other weather proofing soon. I have a tempered glass front lens and a plexiglass front lens for when I need the searchlight to be lighter in weight. The cooling fans provide more than adequate air to keep things cool under 100 degrees on an 80 degree night. I was surprised by how well the bath fans work at only $15.00 Home Depot.


Click here to view the original image of 953x1024px.

More finishing has been done since this photo was taken.

Ready to test after some basic adjustments. Gorilla searchlight now outfitted with 4k watt HMI
The 36 inch Gorilla has been outfitted to operate in inclement weather, a four thousand watt HMI lamp producing over 385,000 lumen light output.


Here's the new 36 inch Gorilla reconditioned into the 4 Kwatt beast it is now. Want to test this at night, but the touchy situation with a neighbor having a fight with her boyfriend means I'll probably have to pack this like sardines into my car and find a parking lot somewhere and not get into too much trouble...lol.

Click here to view the original image of 1600x1242px.

The horizontal bars are from the magnetic ballast lag wave.




Plastic lens works well under the heat, but I wasn't cooling the back reflector enough so it tarnished unevenly into a deep golden color. Will have to work on that, add maybe a forth fan just for cooling some of those critical components, or decide it works well enough for now and make improvements along the way...it's already way super bright..!


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Getting an idea of the beam


Forms a nice tight beam for several hundred feet, but I wasn't able to shine it way out, for fear of disturbing people....I'm going to have to work on this.


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Looks like daylight.



With the performance of the Gorilla adequate, but not as well focused as the Monster will be, with a longer focal length, will make a more collimated beam, though it may not be quite as bright, as it gathers less light by design to get it's incredible focal length.
Had everything set up and by chance many neighbors weren't home and others were up past their bedtime, so I took a quick ten minutes and fired up this bad boy and took some night shots. Beam isn't as well collimated as I wanted, still needs some focus fine tuning, but it still makes a very impressive beam that can be seen for many miles and draws quite the crowd.

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Here's a view from a block away. Very impressive. I'll get better photos as time permits.


Beam as seen from near my shop with searchlight.




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As seen from a block away, The 36 inch Gorilla has been outfitted and upgraded for weather resistance but now Much Brighter at 385,000 lumen.


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Beam looks cool seen through the trees. Dominates the sky and looks quite beautiful. Won't look like UFO's in the clouds, as the beam spreads just enough to still light the clouds, but not so bright and with a beam that can be seen connecting it to it's source for customers to travel joyfully to...lol.


I coudln't go very far as I only had a few minutes, as many people noticed this bright beam in the sky and start to travel towards it. I had to stop the migration before my neighbors got upset over another spotlight traffic jam.


Click here to view the original image of 1024x732px.

As seen from half a block away, The 36 inch Gorilla has been outfitted and upgraded for weather resistance but now Much Brighter at 385,000 lumen.

In the Monster, the beam will travel farther, just not as bright as the beginning, but brighter out towards it's ending part of beam.

Coudln't get too far from the searchlight, as crowds started to gather.

Test at Stores and restaurant openings soon, when the nights are longer again.

 

[Mike V]

I didn't read all the posts in this thread, but are you running a HMI open faced?
Please say you are not.

Also if you like this sort of thing, check out the LightningStrikes 200K PAR, 250K Linear or the 100K SoftSun for cool massive output lights.
Now those things put out a heap of light.

Xenotech 7K Xenon has insane throw and very big output too.

 

[LightSward]

I didn't read all the posts in this thread, but are you running a HMI open faced?
Please say you are not.

Also if you like this sort of thing, check out the LightningStrikes 200K PAR, 250K Linear or the 100K SoftSun for cool massive output lights.
Now those things put out a heap of light.

Xenotech 7K Xenon has insane throw and very big output too.

Some really powerful lights.

Be cool my friend...I wouldn't expose anyone to UV light. Most of my bulbs are single end, UV protected lamps, with additional lenses placed on my most recent creations, offering double protection. Anytime I used a double ended, non UV shielded lamp, I used a UV protection globe and isolated the airflow to the outside to eliminate any hazardous ozone, (O3) created by the UV light onto the breathable form of oxygen, (O2). Have been well aware of UV light from unprotected arc discharge tubes, since the early 1970's when first started playing with mercury vapor lamps and the UV dangers associated with them.

My searchlight beams can be seen in the sky for many miles on a good night, from the 4kwatt lamp.