.MCAD 308000000 \  docDocumentImcObjectW aa d2_graph_format graphData! axisFormat%L%Ltrace2D""""""""" " " " " """ dim_formatPmasslengthtimecharge temperature luminosity substanceNumericalFormatMdii shpRectRmcDocumentObjectStateX mcPageModelG???{?mcHeaderFooterE@E |P  CHeaderFooterFA{\rtf1\ansi\deff0\deftab720{\fonttbl{\f0\fnil MS Sans Serif;}{\f1\fnil\fcharset2 Symbol;}{\f2\fswiss\fprq2 System;}{\f3\fnil\fprq8 Arial;}{\f4\fnil\fprq12 Arial;}{\f5\fnil\fprq6 Arial;}{\f6\fnil\fprq6 Arial;}{\f7\fnil\fprq8 Arial;}{\f8\fnil\fprq2 Arial;}{\f9\froman\fprq2 Garamond;}{\f10\fswiss\fprq15 Arial;}{\f11\fnil Arial;}} {\colortbl\red0\green0\blue0;} \deflang1033\pard\plain\f9\fs16 Elmac Services\plain\f10\fs18 \par } A{\rtf1\ansi\deff0\deftab720{\fonttbl{\f0\fnil MS Sans Serif;}{\f1\fnil\fcharset2 Symbol;}{\f2\fswiss\fprq2 System;}{\f3\fnil\fprq8 Arial;}{\f4\fnil\fprq12 Arial;}{\f5\fnil\fprq6 Arial;}{\f6\fnil\fprq6 Arial;}{\f7\fnil\fprq8 Arial;}{\f8\fnil\fprq2 Arial;}{\f9\froman\fprq2 Garamond;}{\f10\fswiss\fprq15 Arial;}{\f11\fnil Arial;}} {\colortbl\red0\green0\blue0;} \deflang1033\pard\qc\plain\f10\fs18 \{image\} \par } A{\rtf1\ansi\deff0\deftab720{\fonttbl{\f0\fnil MS Sans Serif;}{\f1\fnil\fcharset2 Symbol;}{\f2\fswiss\fprq2 System;}{\f3\fnil\fprq8 Arial;}{\f4\fnil\fprq12 Arial;}{\f5\fnil\fprq6 Arial;}{\f6\fnil\fprq6 Arial;}{\f7\fnil\fprq8 Arial;}{\f8\fnil\fprq2 Arial;}{\f9\froman\fprq2 Garamond;}{\f10\fswiss\fprq15 Arial;}{\f11\fnil Arial;}} {\colortbl\red0\green0\blue0;} \deflang1033\pard\qr\plain\f9\fs16 Consultancy and training in EMC\plain\f10\fs18 \par }  mc_dibitmap 7#(7}EKZ}Ds}}ptttEEE///KKKXXXeeerrr???????????????????????????????????????????????????????????????????????????@FA{\rtf1\ansi\deff0\deftab720{\fonttbl{\f0\fnil MS Sans Serif;}{\f1\fnil\fcharset2 Symbol;}{\f2\fswiss\fprq2 System;}{\f3\fnil\fprq8 Arial;}{\f4\fnil\fprq12 Arial;}{\f5\fnil\fprq6 Arial;}{\f6\fnil\fprq6 Arial;}{\f7\fnil\fprq8 Arial;}{\f8\fnil\fprq2 Arial;}{\f9\froman\fprq2 Garamond;}{\f10\fswiss\fprq15 Arial;}{\f11\fnil Arial;}{\f12\fnil\fprq11 Arial;}} {\colortbl\red0\green0\blue0;} \deflang1033\pard\plain\f9\fs16 http://www.elmac.co.uk \par \plain\f10\fs18 \par } A{\rtf1\ansi\deff0\deftab720{\fonttbl{\f0\fnil MS Sans Serif;}{\f1\fnil\fcharset2 Symbol;}{\f2\fswiss\fprq2 System;}{\f3\fnil\fprq8 Arial;}{\f4\fnil\fprq12 Arial;}{\f5\fnil\fprq6 Arial;}{\f6\fnil\fprq6 Arial;}{\f7\fnil\fprq8 Arial;}{\f8\fnil\fprq2 Arial;}{\f9\froman\fprq2 Garamond;}{\f10\fswiss\fprq15 Arial;}{\f11\fnil Arial;}{\f12\fnil\fprq11 Arial;}} {\colortbl\red0\green0\blue0;} \deflang1033\pard\qc\plain\f12\fs18 \par } A{\rtf1\ansi\deff0\deftab720{\fonttbl{\f0\fnil MS Sans Serif;}{\f1\fnil\fcharset2 Symbol;}{\f2\fswiss\fprq2 System;}{\f3\fnil\fprq8 Arial;}{\f4\fnil\fprq12 Arial;}{\f5\fnil\fprq6 Arial;}{\f6\fnil\fprq6 Arial;}{\f7\fnil\fprq8 Arial;}{\f8\fnil\fprq2 Arial;}{\f9\froman\fprq2 Garamond;}{\f10\fswiss\fprq15 Arial;}{\f11\fnil Arial;}{\f12\fnil\fprq11 Arial;}} {\colortbl\red0\green0\blue0;} \deflang1033\pard\qr\plain\f9\fs16 \{n\} of \{nn\}\plain\f10\fs18 \par } @F@FMbP?MbP? TextState; TextStyle:@ ArialSerial_ParPropDefaultSNormal:@Arial@S Heading 1 :@ Arial@S Heading 2 :@ Arial@S Heading 3 :@ Arial@S Paragraph :@ Arial@SList :@ Arial@SIndent:@Times New Roman@S Title:@Times New Roman@S Subtitlefont_style_listK font_styleL  VariablesTimes New Roman@L  ConstantsTimes New Roman@L TextArial@L Greek VariablesSymbol@L User 1Arial@L User 2 Courier New@L User 3System@L User 4Script@L User 5Roman@L User 6Modern@L User 7Times New Roman@L SymbolsSymbol@L Current Selection FontArial@L Undefined Font@L HeaderArial@L FooterArial@L Rotated Math FontTimes New Roman TextRegion& docRegionCshpBoxQ!82#  CharacterMap)RangeMap7Chamber and enclosure resonance ChrPropMap3 ParPropMap5 RangeElem8 ParPropData6 RangeData9@SEmbedMap-8LinkMap+8LinkData,@ Heading 1Arial&@QNZ[ )AAny rectangular screening enclosure has resonances in its internal field structure whose frequencies depend on the dimensions of the enclosure. At these resonances standing waves exist in the internal field, leading to wide variations in field strength with position; and maximum currents flow in the walls, so that screening effectiveness is reduced, especially if apertures and discontinuities are present. The resonant frequencies of an empty enclosure of dimensions L, H and W metres are given by3586@S-8+8,@NormalArial eqRegion>@QZ1Vtree < p< <dL <0.78!>@QTa:"< p#< "$<d#i%<#&< @%'<t&1(<&2)<%6*&@Q; 2a a )(example: 19" rack cabinet)35+8,6@S--8+.8/,@NormalArial 0&@Q< )"(or any one at a time can be zero)3"5"18"26@S-38+"48"5,@NormalArial 6>@QT)3"U7< p8< 79<d8H:<81.4;>@QT)a"><< p=< <><d=j?<=@@< @?@A<t@@1@B<@@2@C<?6@D&@Q*Z6C 00)@K(selecting maximum 6th order mode is arbitrary you may want to go higher)3K5K@E8K@F6@S-@G8+K@H8K@I,@NormalArial @J>@Q?WQ6JT@K< p@L< @K@M<d@LW@N<@L0.6@O>@QT?QeJ@@P< p@Q< @P@R<d@Qk@S<@Q@T< @@S@U<t@T1@V<@T2@W<@S6@X>@Qv-_S@Y< p@Z< @Y@[<@@Z@\<d@[F@]@Q(O(Y@< p@<@@<@@@<@@@<@@@<t@0.3@<@0@<@@<@@@<@@< @@< @@@< @@@<@@@<t@1@<@@<@@@