CUSHCRAFT BIG THUNDER XM520, Assembly & Installation

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209
208
207
35
99
209
208
207
207
208
209 3209
3209
209
506
542
208
207
209
208
207
618
35
35
35
Boom Shelf
82
84
209
208
207
209
208
207
506
588
84
99
99
84
82
588
84
99
326
506
ID Part # Description Dimensions Qty
35 170035 Aluminum 3-1/2” 4
V-Block (8.9 cm)
82 010082 Hex 1/4-20 x 1” 16
Bolt (2.5 cm)
84 010084 SS Lock 1/4” 18
Washer (0.6 cm)
99 014399 SS Lock 1/4” 18
Nut (.6 cm)
207 010207 SS Flat 3/8” 8
Washer (.95 cm)
208 010208 SS Lock 3/8” 8
Washer (.95 cm)
209 010209 SS 3/8” 8
Nut (.95 cm)
326 290326 Danger 1
Label
506 324506 Aluminum 8” x 5-1/4” x 3/16” 2
Bracket (20.3 x 13.3 x .5 cm)
542 194542 Alu Mounting 8” x 8” x 1/4” 1
Plate 20.3 x 20.3 x .6 cm)
588 014588 SS Hex 1/4” x 3-1/2” 2
Bolt (.6 x 8.9 cm)
618 194618 Alu Mounting 6” x 12” x 1/4” 1
Plate (15.2 x 30.5 x .6 cm)
3209 013209 U-Bolt 2-7/8” 4
(7.3 cm)
Figure 5B
Figure 5A
The XM520 boom-to-mast clamp is designed to be mounted on the
tower/mast so the built in boom shelf feature can be utilized. Following this
suggestion, if possible, will simplify antenna installation.
Reference Figures 5A and 5B for assembly of boom to mast clamp. Required
hardware is listed in the Boom to Mast Clamp Assembly Parts List. Form
the boom shelf by attaching the lower boom bracket (506) to the mast plate
(542). Attach mast plates (542 & 618) to mast using U-bolts (3209) and V-
blocks (35).
Place the boom on the boom shelf during installation. Loosely attach the
top boom bracket (506) to the mast-plate (542) and to the lower boom
bracket (506) as shown in Figure 5B. This allows the boom to be moved
back and forth for tower top element mounting.
When all elements are securely mounted to the boom and the feed system
is in place, line up the 2 holes in the top of the upper boom bracket (506)
holes with the corresponding 2 holes in boom section BC. Insert bolts (588)
and tighten in place. Next, tighten the 8 bolts, securing the upper and lower
boom brackets. Tighten the 4 bolts connecting the upper boom bracket to
the mast plate.
Attach good quality coax with a PL-259 connector to the XM520 matching
network. Route the coax as shown in Figure 3B. Form a drip-loop with the
coax and secure the coax to the boom. Insure PL-259 connector is
waterproofed with a good quality sealant after it is attached to the matching
network.
9
5-Boom to Mast Clamp Assembly