Hello Dave, I read that using an aluminized mylar shield will block visible light to a photodiode, do you think this will work for a solarcell? I have a few about the size of a pencil eraser available. I'm trying for gamma/alpha/beta higher-energy stuff. Alice Find the best deals on the web at AltaVista Shopping! http://www.shopping.altavista.com -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body