Your Cushcraft MA5B Yagi is designed and manufactured to give trouble free service. This antenna will perform as specified if the instructions
and suggestions in this manual are followed and care is used in the assembly and installation. When checking the components received in
your antenna package use the parts listed beside each diagram. There is a master parts list on page 2. If you are unable to locate any tube
or component, check the inside of all tubing. IMPORTANT: Save the weight 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.
PLANNING
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 the boss and that they must follow your instructions. If you have any doubts at all, employ a professional antenna
installation company to install your antenna.
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. EXTREME CARE MUST BE USED FOR YOUR SAFETY. YOU MUST INSURE THAT WHILE THE MA5B IS
IN OPERATION NEITHER PEOPLE OR PETS CAN COME IN CONTACT WITH ANY PORTION OF YOUR ANTENNA. DEADLY VOLTAGES
AND CURRENTS MAY EXIST. ALSO, SINCE THE EFFECTS OF EXPOSURE TO RF FIELDS 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 I.
MOUNTING
The mast mount bracket will accommodate up to a 2" (5.1 cm) mast. A 1-1/2" OD (3.8 cm) or larger heavy wall tubing mast should be used. 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 a minimum, place your antennas as far apart as you can.
SYSTEM GROUNDING
Direct grounding of the antenna, mast and tower is very important. This serves as protection from lightning strikes and static buildup, and from
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 #10AWG ground wire and noncorrosive
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 6. After the antenna is completely assembled, verify
dimensions and element spacings for accuracy. Then, return to the section below for final tuning.
TUNING PROCEDURE
Set the element lengths for the portion of the band you want to operate on using Chart A and Figure 2. Your MA5B is now ready for use.
You may check the VSWR in order to confirm assembly was done properly. The easiest place to check the antenna is likely to be in its final
mounting configuration. Orient the antenna such that it is pointing straight up. The back of the antenna should be at least 2 feet (.6 m) off the
ground.
Run the coax cable from your transmitter to the area in which the antenna is 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. (305 cm) or less] from the VSWR bridge
to the antenna under test. Set the transmitter to your center operating frequency and measure the VSWR while taking care not to effect the
measurement with your body. A VSWR of 2:1 or less is satisfactory and will not degrade the performance. If the VSWR is greater than 2:1,
check all dimensions and connectors.
WARNING
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.
MA5B
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