It uses a normal 120 to 6V stepdown transformer in reverse to step 12V to about 350V to drive a lamp without the need to warm the filaments.
Q1 must be installed on a heat sink. A 240V to 10V transformer will work better then the one in the parts list. The problem is that they are hard to find. This circuit can give a nasty (but not too dangerous) shock. Be careful around the output leads.
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