Ken: Just posted to my web site an updated PDF for the Samlex SEC 1223, showing the 120VAC to 220VAC jumper location: http://www.n0ss.net/samlex_1223.pdf And the additional RFI reduction mods (if required) are: http://n0ss.net/samlex_1223_rfi_mods_from_zl2df.pdf 73, Tom N0SS