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Antenna Television/Outdoor Antennas

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In suburban or fringe reception areas where higher-gain antennas are required for adequate TV reception, outdoor directional antennas are commonly used. Unlike simple antennas with broad response patterns, directional antennas have almost unidirectional radiation patterns and must be pointed towards the TV station. These antennas, based on designs like the Yagi-Uda or log-periodic dipole array (LPDA), consist of multiple half-wave dipole elements mounted on a support boom. They provide higher gain and narrower radiation patterns. Reflective array antennas are also used for UHF reception, featuring a vertical metal screen with dipole elements in front.

Since TV broadcast bands are too wide for a single antenna, separate antennas for VHF and UHF bands or combo VHF/UHF antennas are used. VHF elements are located at the back of the boom, functioning as log-periodic antennas, while shorter UHF elements are located at the front, acting as Yagi antennas. In cases where TV stations are located in different directions, multiple directional rooftop antennas can be mounted on the same mast and connected to one receiver, using filters or matching circuits to maintain performance. Alternatively, a single antenna mounted on a rotator can be used, allowing the antenna to be remotely rotated towards different directions.

In some instances, TV transmitters are strategically placed so that receivers in a specific region only need to receive transmissions within a narrow band of the UHF television spectrum from the same direction. This allows for the use of higher gain grouped aerials.

In TV antenna installations, height is a crucial factor due to obstructions near the ground that can disrupt TV signals. Electrical noise from digital electronics can also interfere with reception. Mounting the antenna on a tripod and mast above the roof line by an additional 12 feet can help overcome these issues, especially in areas with buildings of similar height. If channels are lost, it is advisable to inspect antenna connections for any issues such as rust or corrosion regularly.

Common Outdoor Antennas

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UHF Band Antennas

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Four Bay UHF Type

The four bay UHF type of antenna stands out because it offers both high gain (9 dB) and a wide beamwidth (60°). This unique combination makes it an exception to the typical trade-off between directionality and gain in antennas. It is particularly useful in scenarios where all channels are in the UHF band and especially when those channels are spread out over a wide arc.

  • Digiwave ANT2084, ANT2085
  • Stellar Labs 30-2426
  • Solid Signal XS HDB4X AKA Digiwave ANT2086
  • Channel Master CM4221HD
  • Antennas Direct DB4e
  • Antennas Direct 4 Max

Two Bay UHF Type

The two bay UHF type antenna does not offer any advantages over the four bay UHF type antenna and has half the gain. It should only be considered in cases where space or appearance constraints make it impossible to install a four bay UHF antenna.

  • Digiwave ANT2088 AKA Solid Signal XS HDB2X AKA Stellar Labs 30-2420
  • Antennas Direct Clearstream 2
  • Channel Master CM-4220HD
  • Eagle Aspen DTV2BUHF

Eight Bay UHF Type

The eight bay UHF antenna is known for its high gain and is considered one of the antennas with the highest gain available. It is particularly suitable for situations where UHF signals are weak. Some eight bay antennas can be split and aimed in two directions, enabling you to receive signals from multiple directions. However, it's important to note that splitting the antenna will reduce its gain and strength. Without using an amplifier, you can typically expect a gain of 12dB to 16dB from the eight bay UHF antenna.

  • Digiwave Ant7285
  • Solid Signal HDB8X AKA Digiwave Ant7288 AKA Stellar Labs 30-2431 (adjusted flat)
  • Channel Master CM4228HD (supposed to have some VHF-high capability)
  • Antennas Direct DB8e (adjusted flat)

Yagi-Uda UHF

The higher gain versions of Yagi-Uda UHF antennas have performance that is comparable to the eight bay UHF type. The choice between them can be controversial, as they have different shapes that can impact their suitability in specific cases.

UHF and VHF-high Band Antennas

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Most television channels in North America are carried on the UHF band with one or two in the VHF-high band, making these antennas the most desirable. These antennas are typically larger than a pure UHF type to accommodate for the VHF-high requirement.

Lower Gain UHF/VHF-high

These types of antennas are particularly useful in situations where space or appearance restrictions exist and the signal levels are relatively high. They can be conveniently mounted on a reused satellite dish J-mount.

  • Winegard FV-30BB (Freevision)
  • Antennas Direct Clearstream 2 Max
  • Antennas Direct Clearstream 4 Max
  • Channel Master CM-3010HD (Steathtenna)
  • Winegard HD7000R (without extensions)
  • RCA ANT751

Higher Gain UHF/VHF-high

Higher gain antennas are more directional and require careful adjustment for optimal performance.

  • Winegard HD7694P
  • Winegard HD7698P
  • Channel Master CM-2016 (weak on VHF-high)
  • Channel Master CM-2018
  • Channel Master CM-2020

VHF-high Band Antennas

A separate channel for VHF-high band antennas are sometimes required to receive VHF-high band signals in a different direction from UHF signals.

All Band Antennas

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Some television markets (most notably Philadelphia, PA) have major networks in the VHF-low band. An all band, or all channel, antenna is required for these situations. These antennas can be unusually large compared to other types.

Lower Gain All Band

  • Winegard HD7000R with extensions (weak on VHF-low)
  • Channel Master CM3016

Higher Gain All Band

  • Winegard HD8200U
  • Channel Master CM3018
  • Channel Master CM3020
  • Channel Master CM5020
  • Denny's HD Stacker
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