%!PS-Adobe-2.0
/r 360 26 div def % degrees in each segment
/Tempstr 2 string def % for writing value to a string
/radius 225 def % size of outer circle

/circleofLetters {   
  [(A) (B) (C) (D) (E) (F) (G) (H) (I) (J) (K) (L) (M)
   (N) (O) (P) (Q) (R) (S) (T) (U) (V) (W) (X) (Y) (Z)]
  /ary exch def % the array of letters
  0 1 25{ % from 0 to 25 in steps of 1
    /ind exch def % the for loop value
    /rind ind 0 eq {0} {26 ind sub} ifelse def
    gsave
      ind r mul neg rotate % rotate by (for loop value)*360/26
      /Helvetica-Bold findfont 23 scalefont setfont
      ary ind get stringwidth pop 2 div neg radius 5 sub moveto
      ary ind get show
      % convert ind to string, store in Tempstr, using cvs
      ind Tempstr cvs stringwidth pop 2 div neg radius 25 add moveto
      ind Tempstr cvs show
      3 setlinewidth
      0 radius 30 sub moveto 0 20 rlineto stroke
    grestore
  } for
} def

/circles {
   3 setlinewidth
   newpath 0 0 radius 20 sub 0 360 arc stroke
   newpath 0 0 6 0 360 arc stroke
} def

/doitall {
  newpath 
  -306 -396 moveto 612 0 rlineto 0 792 rlineto -612 0 rlineto
  closepath stroke
  gsave
    -306 -396 translate
    /Helvetica-Bold findfont 15 scalefont setfont
    40 90 moveto (Place arrow of inner circle on pad character.) show
    40 70 moveto (To encrypt, follow inner circle plaintext) show
    ( letter to outer circle ciphertext letter.) show
    /Helvetica-BoldOblique findfont 15 scalefont setfont
    40 50 moveto (To decrypt, follow outer circle ciphertext) show
    ( letter to inner circle plaintext letter.) show
    130 700 moveto (Outer letters belong to the ciphertext or to the pad.) show
    /Helvetica-Bold findfont 10 scalefont setfont
    310 28 moveto (Copyright )show
    /Symbol findfont 10 scalefont setfont (\323) show
    /Helvetica-Bold findfont 10 scalefont setfont
    ( 2002 by Neal R. Wagner.  All rights reserved.)show
  grestore
  /Helvetica-BoldOblique findfont 15 scalefont setfont
  -90 20 moveto (Attach smaller circle here.) show
  circleofLetters
  circles
} def

8.5 72 mul 2 div 11 72 mul 2 div translate
% 0.6 0.6 scale % scale factor for magnification
doitall
showpage