Crossbow III 3-Element Beam CB Antenna
(210-0933)                 Assembly                   Faxback Doc. # 50798

Before you begin to put your Beam Antenna together, here are a few of the
things you should do:

1.  Determine where and how you will install it - with a rotor vertical or
    horizontal, on a free-standing mast or on top of your house or office.

2.  Separate all of the parts - check them against the Parts List - then
    organize them so that all of the same size and type are together.

3.  During assembly, position all medium diameter tubes (illustration No
    7) so the fastening holes are positioned upward (See F for an example).

    A  Locate the two large pieces of tubing, illustration Numbers (5 and
       6).  These are for the Boom.  Locate a slightly thinner piece of
       slotted tubing, 7" long. Deburr the inside edges of the long tubing
       where the weld bead is (use a knife or other sharp edged tool for
       this).  Refer to "A" and attach the Boom pieces to each other by
       sliding the slotted tubing inside each other. Be sure this assembly
       fits snug and tight.

    B  Mount the two Boom-Mast Brackets over the center of the above Boom
       joint - as shown in "B."  Fasten securely with 4 large bolts (one
       at each corner, lockwashers and nuts.  Place the large U-bolts into
       the holes provided and loosely fasten with lockwashers and nuts.

    C  Position the above assembly so the longer end of the Boom is to
       your right (as viewed in the major illustration).  Locate 5 equal
       length medium diameter tubes (illustration No. 7), the Gamma
       Element assembly (8), a saddle bracket and small U-bolts.  Slide
       the end of one of the medium diameter tubes into the open end of
       the Gamma Element assembly (#7 fitting into the end of #8 as shown
       in "C").  Fasten #7 to the Gamma Element tubing with a long screw,
       lockwasher and nut.  Position the Gamma Element over the right end
       of the Boom assembly as shown and mount with a small U-bolt, 2
       lockwashers and nuts.  Before fastening securely, position this
       assembly so it will be spaced 17" from the center of the large
       U-bolts (in the center of the Boom assembly): tighten nuts securely.

    D  Use 2 more of the medium diameter tubes and fasten together using a
       10" large diameter tube (slip medium tubes inside the larger tube).
       Fasten together as shown in "D" using 2 long screws, a saddle
       bracket, small U-bolts and 4 lockwashers and nuts.  Before
       tightening the U-bolt nuts, slip the assembly over the right end of
       the Boom.  This will become the Director Element Assembly: space it
       58-1/4" from the center of the Gamma Element/Driven Element
       assembly and be sure it is parallel with, and on the same plane as,
       the Driven Element Assembly.  Tighten hardware securely.

       Assemble the remaining medium diameter tubes with a 10" large tube
       in the same manner.  Place over the left end of the Boom and fasten
       as above.  This will become the Reflector Element Assembly;
       position it 65" from the center of the large U-Bolt (where the Mast
       will be).  Be sure this element is parallel with, and on the same
       plane as, the other two elements; fasten hardware securely.

    E  The balance of the tubing is illustrated in "E" and the major
       drawing.  Use the longest thin tubing (#1) and fasten to the ends
       of the Reflector Element Assembly using a self-tapping screw and
       lockwasher with each to secure the ends into #7.  See "F" for an
       illustration of how this screw fits.

       Use the shortest tubing (#4) and fasten to the ends of the Director
       Element Assembly - secure with self-tapping screws and lockwashers
       as above.

    F  There are 2 tubes left-install the sorter one (#3) into the end of
       the Gamma Element (#8) tubing.  The last tube (2) has two holes for
       the screw fastening.  See NOTE 1, below for explanation of which
       hole to use as you fasten this final part in place.

       Note 1:  If you are going to position the Antenna vertically, use
                the first (end) hole in #2 tubing: for horizontal
                positioning, use the second hole.

       NOTE 2:  Install end caps over the ends of the thin tubes if you
                mount the antenna horizontally.  For vertical mounting,
                don't use the end caps over the bottom ends of the thin
                tubes (they would hold rain and moisture inside the

       NOTE 3:  The major illustration shows assembly for horizontal
                positioning.  If you are going to use vertical position,
                loosen the Boom-Mast Bracket assembly and rotate it so the
                Gamma Element will face away from the Mast: then retighten
                the nuts.

(BR/eb 12/3/98)

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