The chain hardware stores sell UV coiled-style bulbs: $8 gets you a 13-watt bulb about 6" high that fits a standard lamp socket. Mount 3 of them on a board with line-cord and an inline switch and put the whole thing in a plastic milk-crate sold at stationery stores for files. Line the inside of the milk-crate with aluminum foil over cardboard, put a contact frame upside-down on top of the milk-crate, and insert a timer in the AC line to the bulbs. Mine works positively great. Exposure times for Pt/Pd printing with the contact frame about 7" above the top of the bulbs is between 3 and 10 minutes, depending. I must admit 4 bulbs might make for more even prints, but I do not notice any hot-spots. Some very minor heat is developed. I have a series of photos if you want to email me. Total cost was under $35, all new materials. I researched LEDs and found that I would need about $100 worth of materials just to see if the LEDs would work. Of course, LEDs are getting cheaper.