Making UV (ultra violet) box/chamber for PCB and other photo sensitive jobs

This is short illustrated, step-by-step instructions how to make UV box very cheaply, quickly and without any exotic components and winding any transformers. Note: this schematics use mains (live) power, so touching to any wire or lamp terminal could be fatal. Tested to work with 220~240V.
Main component: High pressure HID mercury lamp (High Intensity Discharge). Usually they are used to light streets, storage houses and etc. If the light is bluish, and some objects change colors this is Mercury lamp. You can buy it at any good hardware store. Try to get as low power as you can. In this picture is 250W power lamp. Its size about 20cm (8 inch). Do not you Sodium lamps- yellow light lamps. uv06
Breaking UV filter glass.
Inside such lamp there is small UV lamp, outside glass is with special coating to convert UV light to visible. Also glass is thick and filters most of UV radiation. So, wrap the lamp with some rug and smash external glass with hammer. Be careful. There is some pressure inside lamp and glass is quite strong.		 uv05
Inside the lamp.
Now we see some internal components of lamp. There is one or two starting resistors connected to special starting electrodes- do not break or remove. They are about few hundred K Ohms. Take note that lamp in the picture is with very ugly white and black coating. This is because the lamp is very old and after many years of working. According to markings on tube, it is 14 years old! (Some guy told me that old, bad lamps are even better because warn out lamps have more wide spectrum.)
lamp schematics 		uv04
Testing lamp with High Voltage 10,000V
YOU DON'T NEED TO DO THIS. I made a nice photo, so I wanted to share with you :)
This is same lamp connected to 10kV, self ballasting high voltage transformer. This transformer can light almost everything :)		 uv03
Schematics and test connections
You need to find/buy ANY tube lamp (low pressure mercury lamp) ballast. ANY power. In the picture is shown generic 40W ballast. You can use up max power the lamp can handle. In my case it is 250W. But it is too much power for our needs.
UV box schematics 		uv01
Testing lamp and components
Generally, if you connected everything according schematics, it starts. There maybe problems with very old lamps. Simply there maybe to low voltage to start discharge. Try to switch of and on several times. This causes voltage spikes and lamp starts. In worst case you need to add start switch parallel to lamp. Switch off this switch you cause high voltage spike from ballast ant this starts lamp. When lamp start soon you'll smell specific scent of ozone. This means that lamp has enough power to break apart oxygen in the air.		 uv02
Placing parts in the box
Now find some box suitable for your design. I used old wooden box from some old equipment. This box is still under construction as didn't find any suitable plastic to cover lamp. Take note that lamp become hot. Also in this box is used smaller lamp. I needed to add starting resistors by myself. (The big white resistor is not connected to circuit, it simply left from older schematics)		 uv08
Working box
Here is working box with its bluish light. Take note that UV light emited by this device is harmfull for you eyes. 		uv09


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