Cushcraft A44911S Instructions

A449-11

ASSEMBLY AND INSTALLATION

A449-11

70 CENTIMETER FM YAGI ANTENNA

440-450 MHz

COMMUNICATIONS ANTENNAS

951424 (10/91)

A449-11

THIS ANTENNA IS AN ELECTRICAL CONDUCTOR. CONTACT WITH POWER LINES CAN RESULT IN DEATH OR SERIOUS INJURY.
DO NOT INSTALL THIS ANTENNA WHERE THERE IS ANY POSSIBILITY OF CONTACT WITH OR HIGH VOLTAGE ARC-OVER FROM
POWER CABLES OR SERVICE DROPS TO BUILDINGS. THE ANTENNA, SUPPORTING MAST AND/OR TOWER MUST NOT BE CLOSE
TO ANY POWER LINES DURING INSTALLATION, REMOVAL OR IN THE EVENT PART OF THE SYSTEM SHOULD ACCIDENTALLY
FALL. FOLLOW THE GUIDELINES FOR ANTENNA INSTALLATIONS RECOMMENDED BY THE U.S. CONSUMER PRODUCT SAFETY
COMMISSION AND LISTED IN THE ENCLOSED PAMPHLET.

Your Cushcraft A449-11 antenna is designed and manufactured to give top performance and trouble free service. The antenna will perform as
specified if the instructions and suggestions are followed and care is used in assembly and installation. When checking the components received
in your antenna package use the parts lists in each section. It is easiest to identify the various dimensions of tubing by separating them into groups
of the same diameter and length. If you are unable to locate any tube or component, check the inside of all tubing.

label from the outside of the carton. Each antenna is weighed at the factory to verify the parts count. If you claim a missing part, you will be asked
for the weight verification label.

There is a master parts list on page 2.

WARNING

IMPORTANT: save the weight

LOCATION

Location of the antenna is very important. Surrounding objects such as trees, power lines, other antennas, etc. will seriously reduce efficiency. To
minimize the effects of surrounding objects, mount the antenna as high and in the clear as possible. If metal guy wires are used, they should be
broken with strain insulators. YOU MUST INSURE THAT NEITHER PEOPLE NOR PETS CAN COME IN CONTACT WITH YOUR ANTENNA
WHILE IT IS IN OPERATION. DEADLY VOLTAGES AND CURRENTS MAY EXIST. ALSO, SINCE THE EFFECTS OF EXPOSURE TO RF ARE
NOT FULLY UNDERSTOOD, LONG TERM EXPOSURE TO INTENSE RF FIELDS IS NOT RECOMMENDED. THERE IS A WARNING STICKER
WHICH MUST BE ATTACHED TO THE BOOM AS SHOWN IN FIGURE E.

Plan your installation carefully. If you use volunteer helpers be sure that they are qualified to assist you. Make certain that everyone involved
understands that you are in charge and that they must follow your instructions. If you have any doubts at all employ a professional antenna
installation company to install your antenna.

MOUNTING

The A449-11 mast mount bracket will take up to a 1-3/4" (4.4 cm) O.D. mast. A 1-1/4" (3.17 cm) television type tubing is satisfactory for any of the

single

beams. A good heavy-duty antenna rotator will provide the best service and longest life. Often it is desirable to mount several antennas

on one mast. To keep possible interaction to minimum, place your antennas as far apart as you can. Mount the A449-11 with the

rod pointing up.

from the mast. See page 5 for dual array configuration.

Keep the mast mount bracket on the opposite side of the boom from the elements. This will help to minimize pattern distortion

Reddi-Match

SYSTEM GROUNDING

Direct grounding of the antenna, mast, and tower is very important. This provides protection from lightning strikes, static buildup, and high voltage
which is present in the radio equipment connected to the antenna. A good electrical connection should be made to one or more ground rods (or
other extensive ground system) directly at the base of the tower or mast, using at least #10 AWG ground wire and non-corrosive hardware. For
details and safety standards, consult the National Electrical Code. You should also use a coaxial lightning arrester. Cushcraft offers several different
models, such as LAC-1, LAC-2, and the LAC-4 series.

ASSEMBLY

Assemble your antenna by following the directions and illustrations in steps 1 through 5. After the antenna is completely assembled, verify
dimensions and element spacings for accuracy. Then, return to the section below for final tuning.

TUNING PROCEDURE

The A449-11 does not normally require tuning after assembly. However, if you wish to check the VSWR before installation, please observe the
following procedures. To prevent detuning the antenna, it should be tuned in place or at least 7 feet (2.1 m) above ground and clear of surrounding
objects. Keep all metal obstructions such as guy wires and other antennas at least 7 feet (2.1 m) away since they will nullify any adjustment and
degraded performance will result.

Run the coax cable from your transmitter to the area in which the antenna is going to be tested. The length of this cable or your feedline is not critical.
Connect a good quality VSWR bridge to the end of this cable. Connect a short length of cable [10 ft (3 m) or less] from the VSWR bridge to the
antenna. Set the transmitter to your center operating frequency. When you read VSWR, be sure you move far enough away from the antenna
so that your body does not effect the reading.

Measure the VSWR. If it is high, move the Reddi-Match clamp by 1/4" (.6 cm) in one direction and check the VSWR. If the VSWR improves, then
continue moving the Reddi-Match clamp in the same direction. If the VSWR deteriorates then move the Reddi-Match clamp in the opposite direction.
Repeat this procedure until no further improvement can be made. You have matched your antenna to 50 Ohms. Tighten all connections making
sure to keep the Reddi-Match assembly parallel to the element (EB) above. Tape the feedline to the boom and mast (figure G).

1

A449-11

MASTER PARTS LIST

11 010011 8-32 stainless steel hex nut 13
26 190026 7/8" x 1-1/2" (2.2 x 3.8 cm) mounting bracket 11
28 190028 Aluminum half washer 10
32 190032 3-5/8" x 2-1/2" (9.2 x 6.3 cm) U-bolt bracket 1
38 050038 1" (2.5 cm) black plastic cap 2
41 011941 #8 stainless steel lock washer 14
53 050053 1/2" (1.3 cm) black plastic cap 2
79 010079 8-32 x 1/2" (1.3 cm) stainless steel machine screw 1
84 010084 1/4" (.63 cm) stainless steel split lock washer 2

85 010085 1/4" (.63 cm) stainless steel nut 2
115 050115 Connector boot 1
116 240116 Silicone package 1
231 010231 8-32 x 1-3/4" (4.4 cm) stainless steel machine screw 10
232 010232 8-32 x 2-1/2" (6.5 cm) stainless steel machine screw 1
251 050251 3/8" (.9 cm) white plastic cap 1
326 290326 Danger label 1
402 010402 3-3/4" x 1-3/4" (9.5 x 4.4 cm) stainless steel U-bolt 1
720 190720 7/8" x 3/8" (2.2 x .9 cm) backing plate 1

KEY PART # DESCRIPTION QUANTITYKEY PART # DESCRIPTION QUANTITY

921 200921 Reddi-Match clamp 2
941 360941 #8 aluminum flat washer 2

BA 1" x 53" (2.5 x 134.6 cm) aluminum tubing drilled 15 places 1
CB Connector bracket 1
EA 13-1/8" (33.3 cm) element rod 1
EB 12-3/8" x 1/2" (31.4 x 1.3 cm) aluminum element tube 1
EC 11-3/4" (29.8 cm) element rod 1
ED 11-5/8" (29.5 cm) element rod 1
EE 11-1/2" (29.2 cm) element rod 1

EF 11-3/8" (28.9 cm) element rod 1
EG 11-1/4" (28.6 cm) element rod 1
EH 11-1/8" (28.3 cm) element rod 1

EI 11" (27.9 cm) element rod 1

EJ 10-7/8" (27.6 cm) element rod 1
EK 10-3/4" (27.3 cm) element rod 1
PT 3/16" x 2" (.5 x 5.1 cm) poly tube 1

RR 3/16" x 1-5/8" (.5 x 4.1 cm) Reddi-Match rod 1

RT 3/8" x 2-3/4" (.9 x 7.0 cm) aluminum tube 1

#1 - BOOM ASSEMBLY

To make sure that the elements are mounted on the boom in the proper sequence it is necessary to determine the front and back of the boom (figure
A). The larger U-bolt mounting holes are not in the center of the boom. There are six element holes on one side of the U-bolt mount holes and
five on the other. The driven element will be mounted on the side with 5 holes which is the back of the boom. Press end caps onto the ends of
the boom.

FIGURE A

53"

(134.6 cm)

23-1/2"

(59.7 cm)

5 ELEMENT HOLES

38

BACK

Driven element (EB) mounts here.

KEY P/N DISPLAY DESC SIZE QTY

BA

27-3/4"

(70.5 cm)

6 ELEMENT HOLES

FRONT

38

BA ALUM 1" x 53" 1

TUBE (2.5 x 134.6 cm)

38 050038 PLASTIC 1" 2

CAP (2.5)

2