Mobile antenna: Difference between revisions
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== Pedestrian Mobile == | == Pedestrian Mobile == | ||
Antennas for handheld transceivers tend to be limited due to space constraints, with vertical antennas of 1/4 wavelength (at VHF) or smaller commonly used. | |||
== Mobile Antenna Design == | == Mobile Antenna Design == | ||
Revision as of 07:40, 4 June 2009
Mobile antennas are designed to be used for operation while in motion. Their uses include pedestrian mobile operation while walking, bicycle-mounted antennas for use while riding, and the most common form, automobile-mounted antennas for use while driving.
Mobile antennas should not be confused with portable antennas, which are designed to be easy to transport and set up, but are not used while in motion.
Automobile Mobile
Mobile antennas for automobiles are usually verticals of limited height. They must allow the vehicle to be driven under an overpass or tree branch without damaging the antenna or vehicle. A common maximum height for this type of antenna is 13 feet 6 inches (410 cm). On VHF and higher frequencies this is not difficult, but HF requires that mobile antennas be loaded.
Pedestrian Mobile
Antennas for handheld transceivers tend to be limited due to space constraints, with vertical antennas of 1/4 wavelength (at VHF) or smaller commonly used.
Mobile Antenna Design
Capacity Hats
Refer to KE4UYP's article on Capacity Hats.
| Antennas | |
| Design | Beam * Dipole * Dish or Parabola * DDRR * Log Periodic (LPDA) * Loop * Mobile and portable * Omnidirectional * Panel * Quad and Quagi * Screwdriver * Small tuned loop * Vertical * Yagi-Uda * Wire and random wire antennas |
| Installation | Antenna Tuners * Capacity hats and loading coils * Cavity filters * Coaxial Cable * Feedlines * Rotators * Towers and Masts * VK2ACY - G5RV coupler |
| Theory | Front-to-back ratio * Impedance matching * SWR * Tower design * Vertical Antenna efficiency * Wire comparison tables |