4820 Deer Creek way, Paso Robles, CA. 93446
phone/fax 1-805-239-1932
Email: Martronics@TCSN.net
DISCONE ANTENNA
Assembly Instructions
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ASSEMBLY INSTRUCTIONS
DSC-30 and DSC-13 Discone antenna Preassembly requirements: 1/4" and 3/8" end wrenches, or screw driver. supplied alien hex wrench set. knife, pipe wrench set, wire cutter. a crimping tool, or modify the wire joints with small split splice bolts, (aka kemy) and an adjustable mast or crank up tower. and if mast clamps are supplied, obtain the proper wrenches to secure the clamps. 1) To set up the top hat hub on a supported galvanized 1 /2" standard threaded mast pipe about head height. First feed the Coaxial cable through the pipe and securely connect the coaxial cable connector to the hub base N .,connector, with a strong hand, no pliers. Then tighten the Hub to the pipe by turning the pipe onto the hub, and securing with pipe wrenches, check beforehand to insure the set screws are in place. If the antenna is to be installed permanently, I recommend using some form of locktite 242 or permatex thread sealer on all of the screws and bolts, along with aluminum penetrox. in the element sockets. Insert and secure the top hat elements or spokes into the 12 sockets. tighten the set screws so they will not 'work loose, (pretty tight), or there may become a missile launched from the antenna in strong winds. the spokes are approximately a yard long, for the DSC-30, and 6 feet long on the DSC-13. Some larger models of antennas have almniclad wire to feed through holes drilled through the ends of the top hat and skirt tubing. Feed the shorter length of almniclad wire through each end of the element hole, making -sure the holes are lined up horizontally. or so the wire feeds without being kinked, and slides freely on the element. Each element should have an approximate equal amount of wire on each side. Using a wire butt connector supplied crimp the two ends together securely after trimming. Like wise after sure there is no slippage in the inner tube after tightening. If It should not tighten enough, or to your satisfaction, remove the tube, and sand the slit on the 1/2" tube, and reinsert the 3/8" tube and tighten the clamp. Make sure that all the elements are adjusted as close as possible to the same lengths. a) DSC-13 Likewise, on the larger antenna there are three tubes, 2 ea 7feet long, and one 6 feet long, when securing these units, extend them all the way out of the outer tube, and reinsert the smaller tubes into the outer tubes about (3 ") or about a finger length will be fine. b) After extending the second set of tubes on the DSC-13 find a set of short snap together tent poles and fit them all together, if you are making a permanent installation, I recommend using a bit of R TV rubber to secure the pieces together. after they are all secured in a straight line, bend them in a hoop around the antenna mast, being careful not to let go of the two end mini bungi cords, tie them together with a (sheet bend) knot, (find a boy scout) if your not sure. fit the ends together. and raise the hoop into the inside of the cone and secure it with two each black tie wraps crossing each other, and ~ with wire cutters, on each cone element, about 1- 112 feet up the element ;so the element angle at the apex is as close to 60 degrees as possible. this angle helps set the (z) of the antenna. and also keeps the elements from vibrating too much and blowing in the wind. c) Now as before secure the 3/8th's inch tubing as before about 3 inches into the 1/2 inch tubing, being sure that all the end holes line up as before. feed the bottom alumiclad wire through each element insure that is slips freely through the tubing. be sure to have safety glasses on when handling the wire. J) DSC-30 Raise the mast to the approximate height that the skirt "elements are long, and standing on a short step ladder, insert and like before ,secure each of the skirt elements into the angled lower hub section. tighten and make sure there is no slippage before final erection. wiggle each element .to insure proper seating, and tightening each one, double check all of the set screws. put some healthy torque onto each socket set screw. 4) The mast should be long enough to get the antenna over the top of any interfering obstructions. any obstruction made of metal that passes through the skirt elements will cause interference to the antennas resonance where the obstruction passes through. 5) Be very careful, to avoid all power lines. Use proper rigging equipment and think each operation through before installing the antenna. If you have any questions, about installing these units, please call Dave at Martronics at the above phone number, before erection of the units. The sag angle will detennine the low end frequency roll off and impedence at the feed point be sure to get the angle as close as possible. If you find I have left any operations out in the instructions please email or call me so the instructions can be updated. Each of your antennas have been fully assembled on my test tower, and tested before shipping to insure ease of assembly and that all of the components are in good condition. If you experience any problems let me know immediately. 'the roll off frequency on the DSC-13 in about 13.5 MHz and can vary a little. on the DSC-30 the 3: about, 1300 MHz. swr is at about 30 MHz. both antenna will work up to. |
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