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Does a dipole have to be straight?
Dipole antennas need not be installed in a horizontal straight line. They are generally tolerant of bending, sloping or drooping as required by the antenna site. Remember, however, that dipole antennas are RF conductors. (So does the coax shield, unless it is routed at 90° from the antenna.)
Does a random wire antenna have to be straight?
The wire may be straight or it may be strung back and forth between trees or walls just to get enough wire into the air. Such antennas are usually not as effective as antennas whose length is adjusted to resonate at the wavelength to be used.
How does a folded dipole antenna work?
The folded dipole antenna consists of a basic dipole, but with an added conductor connecting the two ends together. This makes a ‘loop’ of wire that is a short circuit to DC. As the ends appear to be folded back, the antenna is called a folded dipole antenna.
What happens when you bend a dipole antenna?
The current distribution in a dipole is shaped like a half-cycle of a sinusoid, with maximum current at the center and zero current at each end. Bending the ends down causes the portions of the antenna with low current levels to be vertically phased, but does not change the total harmonic length of the antenna.
Does a random wire antenna need a balun?
A better ground would be multiple radials, or multiple counterpoise wires. If the voltage on the counterpoise or radial ground system is large enough to present a low impedance, station equipment and the antenna ground systems can be tied together. Isolation, such as a current balun, might not be required.
How long is a 10m dipole antenna?
The Wire Size can range from 16 AWG to 12 AWG. The larger the wire, the wider the bandwidth. The antenna is designed to be fed with 50 or 75 Ohm Coax Cable of most any length with a Balun. Place a 1:1 Balun on the Antenna end of the Feedline….Dipole Antenna Calculator.
| 20 Meters | ||
|---|---|---|
| 10 Meters | ||
| 28.000 | 16.71 | 8.36 |
| 28.500 | 16.42 | 8.21 |
| 29.000 | 16.14 | 8.07 |
What makes a dipole antenna a balanced antenna?
A dipole is a balanced antenna, meaning that the “poles” are symmetrical: They’re equal lengths and extend in oppo- site directions from the feed point. In its simplest form, a dipole is an antenna made of wire and fed at its center as shown in Fig 1.
Do you need a straight line for a dipole antenna?
Dipole antennas need not be installed in a horizontal straight line. They are generally tolerant of bending, sloping or drooping as required by the antenna site. Remember, however, that dipole antennas are RF conductors. For safety’s sake, mount all antennas away from conductors (especially power lines),…
What makes a dipole different from a monopole?
(In contrast, a monopole has a single element, usually fed against ground as a vertical.) A dipole is a balanced antenna, meaning that the “poles” are symmetrical: They’re equal lengths and extend in oppo- site directions from the feed point. In its simplest form, a dipole is an antenna made of wire and fed at its center as shown in Fig 1.
Do you have to prune wire to make a dipole?
Most dipoles require a little pruning to reach the desired resonant frequency. Here’s a technique to speed the adjustment. How much to prune: When assembling the antenna, cut the wire 2 to 3% longer than the calculated length and record the length.