Original poster: "Loudner, Godfrey" <gloudner-at-SINTE.EDU> The smaller size is in line with being a high frequency machine. Godfrey Loudner but why so big?, a mate of mine has got a 150kv 500ma, (from an xray machine that was ripped out of the local hospital and thrown up the dump), and it would be 1\5th the size of that. regards richard australia