Jay Holben The next in line on our examination of lighting fixtures is the PAR, which is an acronym for Parabolic Aluminum Reflector. The classic PAR is a reflector and lamp all in one. It is a sealed ...

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For the longest time now, I’ve wanted to build a real, proper radio telescope. To me, this means a large parabolic reflector, a feed horn made of brass sheet, coat hanger wire, and at least for the ...