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dipole
antenna...
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Dipole Lengths for Ham
Bands |
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Length a 1/2 wave antenna (ft)= 468 /
freq(MHZ) |
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Band |
Freq |
Total length |
Leg length |
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10 |
28.4 |
16' 6" |
8'
3" |
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15 |
21.1 |
22' 2" |
11' 1" |
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20 |
14.1 |
33' 2" |
16' 7" |
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40 |
7.1 |
65' 10" |
32' 11" |
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80 |
3.6 |
130' 0" |
65' 0" |
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Description |
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A Dipole -
A wire antenna whose length is 1/2 the transmitting wavelength. The
radiation pattern of a dipole is strongest at right angles. Baluns
should be used at the feed point when the dipole is used with
coax. . |
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Construction |
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Wire
# 12
wire works fine. The strongest wire to use is copper weld. Hook up
wire, speaker wire or even ac lamp cord are suitable only for quick
temporary installations. |
| Insulators
Wire
antennas must be insulated at the ends. Commercially made insulators are
made from ceramic, glass or plastic. They can be purchased at most
hamfests or electronic stores. Home made insulators are perfectly
acceptable and fun to make. Some excellent materials that can be used
are acrylic sheet or rod, PVC tubing, wood, fiberglass rods or stiff
plastic. Any suitable insulating , non conductive material is fine. |
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