On Fri, Oct 15, 2010 at 6:46 AM, Richard Prosser wrot= e: > I haven't made one but we have some small ones here at work that don't > look too difficult to copy. > > I'd start with an old microwave oven and add absorbent material. The > hardest part may be finding something suitable. The boxes we have here > are lined with a carbon loaded foam (at least that's what it looks > like) =A0but we still get reflections from it. You have to be careful to > position the DUT in exactly the same location each time & not rely on > the results too much! (Final tests are done in a proper chamber). > > If you can afford it, I think it's a case of bigger is better, and the > more absorbent material you can squeeze in the better also. Interesting. I thought all these chambers were worth half a million to several million US dollars. But I was only thinking of standard 3m and 10m chamber for EMC/EMI testing. Our 3m chamber is under construction so that I can avoid to go for evening testing in outside test lab. --=20 Xiaofan --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .