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Old 2005-11-16, 02:12 PM   #3
stampeder
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Join Date: Jan 2005
Location: North Delta, BC (96Av x 116St)
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Default Antenna Buying Tips

Do you have some antenna buying tips?
Antennas are designed along well known electromagnetic principles that predate HD, SD, DTV, etc. by almost a half century. Any vendor that claims that a particular antenna model is "better for HD" etc. etc. is full of it. Don't pay attention to that misleading sales & marketing nonsense. The original Channel Master 4228, for instance, is one of the highest rated UHF antennas out there today for all analogue and digital reception, yet its design is about 30 years old! Channel Master has replaced it with the 4228HD, which may mislead people into believing that it is better for HD when in fact independent research proves that it is weaker than the original that it replaced.

Avoid the hype... just the facts, ma'am.

In some central urban areas, such as atop a high rise in downtown Toronto, a set of cheap Canadian Tire rabbit ears might do the job if you just want the local digital and analogue stations, but in other urban areas, rural locales, and deep fringe areas there are a lot of things to consider before purchasing a TV antenna.

Keep in mind that TV antenna technology is essentially the same as it has been for several decades since the laws of electromagnetism and physics apply equally then as now, so this means we are fortunate that there is a body of real world knowledge and evidence about antenna designs and capabilities if you know whom to ask. There are enough real world examples out there for the experts to give you the best advice and save you a lot of trouble. Advice can be found here in the OTA Forum for those difficult situations or possibly pricey decisions. Don't be timid about asking newbie questions.

So, avoid impulse buys based on advertising claims (especially about reception range!) and ignore any claims of an antenna being "Digital Ready" or "HD Compatible" because those terms mean nothing. Never, never buy an antenna because it "looks great" on top of your TV. Getting the best reception is what its all about.
Essential buying and planning tips for OTA antennas:
  • All OTA antennas are "digital ready" and "HDTV ready" (ignore those marketing words)
    • TV antennas of every kind just pick up signals whether they are broadcast in digital or analogue form
    • in theory reception of equal strength analogue signals versus digital signals (all other things being equal too) would therefore be exactly the same
    • in the real world many issues unrelated to the antenna can make such signals differ, as discussed in this OTA FAQ
    • the antenna itself handles both types equally
  • Mount antennas outdoors and as high as possible, free from obstructions
  • Attic or indoor mounting can present reception problems due to signal losses so they should be a last option
  • Most DTV stations are in the UHF band but some are in VHF
  • VHF and UHF antennas are different in size and shape because they receive different frequency bands
    • VHF has 2 bands:
      • VHF-LO contains channels 2 through 6 (54 to 88 Megahertz) requiring a huge antenna
      • VHF-HI contains channels 7 through 13 (174 to 216 MHz) requiring a large antenna
    • FM Radio (88 to 108 MHz) is in between VHF-LO and VHF HI so most VHF TV antennas are also excellent FM Radio antennas, referred to as VHF/FM and capable of also receiving HD Radio (Hybrid Digital) FM stations in CD audio quality from U.S. border areas
    • UHF band contains channels 14 through 69 (470 to 806 MHz) requiring a relatively small antenna
  • Combo antennas feature a UHF and a VHF on one spar
  • For consumers a Combo offers good performance with simpler installation and less room on the mast
  • Pros and OTA hobbyists prefer the performance of separate UHF and VHF/FM antennas rather than a Combo
  • Satellite Dishes cannot be used to receive OTA signals because they operate on totally different frequencies
Is there a warning list of OTA stuff that I should never buy?
Yes, there is a humourous thread called Wacky, Tacky OTA Gear (What NOT To Buy!) that is well worth reading to help you avoid wasting your money on junk and OTA gear NOT to buy. Avoid gimmic antennas such as the ill-conceived Terk 55, the fraudulent Xium Air, or the ones that promise to turn your household AC wiring or aluminum eaves troughs into a TV antenna. Additionally, the OTA Clone & Coat Hanger Antennas - Avoid Most Of Them thread warns of cheap "clone" antennas that may look like high performance models but are usually poor performers.

If you are unsure about a product, the OTA Forum has many threads that deal with specific items and/or brands in which you can read or offer advice. A fool and his money are soon parted.
Can I just go to my local consumer electronics store for OTA stuff?
Yes, some of those stores have some OTA equipment and OTA-savvy knowledgeable staff, but in Canada it generally seems that retail salespeople do not tend to be well briefed on Digital OTA. You can read through the Popularizing OTA HDTV In Canada thread to get a better understanding of the OTA popular awareness situation. For this reason we recommend dedicated, knowledgeable OTA vendors for your parts, sales, service, and installations.
Is it okay to use an old antenna?
Oxidation may be a problem on many old antennas if it is causing welded or soldered joints to fail. If your antenna is still solidly constructed you are fine to clean it with steel wool. I would use something like an SOS or Jet pad for that. Clean the feed points too (where the balun is connected) and replace the old wingnuts or screws with new ones.

As for reception, oxidation will reduce the antenna's effectiveness but it would happen over a long time from when it was new, not suddenly. If you were to take a perfectly new version of the same antenna and compare it side-by-side with your older one you might see some difference in the resulting signal strength, but not at a worrisome level. I have an old-timer 4-bay bowtie reflector on my roof that was almost white with oxidation but I did not hesitate to use it after a cleanup and it works beautifully.
Can I put up my own antenna?
Absolutely, and Post #21 of this FAQ gives a variety of useful tips and links to discussion threads about important antenna installation topics. For those who do not wish to put up their own antenna and OTA gear, experienced, professional installers can be found in almost any part of Canada and the United States.
An Overview of Various Antenna Types
As you read through your printed-out Antenna Chart, here is further info on the most highly regarded consumer antennas. If you cannot locate one for purchase, try to find the next highest one rated on the Antenna Chart:
  • VHF/FM-Only: does not receive UHF stations but receives locally available VHF TV Channels 2 through 13 and FM Radio stations
  • VHF-HI-Only: receives locally available VHF-HI TV Channels 7 through 13
  • VHF/FM/UHF: is called a "Combo" and is capable of receiving all locally available TV channels and FM Radio stations
  • VHF/FM/UHF Deepest Fringe: It is best to leave this category to pros or experienced OTA hobbyists. Mount 2 UHF antennas in stacked configuration (see Post #16 in this FAQ) with a VHF/FM, feeding them into a high-gain all channel preamp atop a minimum 20 foot tower or similar elevation with unimpeded signal from the target. A heavy duty rotor and/or mount is advised due to the weight and wind load. NOTE: A Deepest Fringe setup is NOT suitable for closer use because its great reception power can overload and/or damage amps, TVs, and receivers if proper safeguards are not in place.
  • Metro/Suburban, Condo, RV, or Apartment:
    • Outdoor antenna products like the costly Winegard Square Shooter, the Super Delhi, the pricey Antennas Direct Lacrosse, or the Channel Master 3010A-Stealth antennas have been introduced to be esthetically suitable (smaller) although they are often no match beyond the near fringe range for mainstream antenna gear.
    • UFO-style omnidirectional antennas like the Antennacraft 5MS921 Omni-State, Winegard MetroStar, or Channel Master SmartTenna are useful on Recreational Vehicles and boats, but are prone to suffer from multipath signal interference more than standard antennas. In Canada the one and only location in which I would consider a UFO antenna as a viable alternative to a standard antenna is in the central and northern part of the Niagara Peninsula in Ontario since the Toronto, Hamilton, and Buffalo stations surround the area and are relatively equal in signal strength.
    • Clip-on satellite dish OTA antennas rarely offer anything but extremely local performance so should be avoided.
    • Indoor Antennas: See Post #6 in this FAQ
    • UHF-Only: See the section immediately below.

UHF-Only Antennas
Here's what the antenna pros have found over the years about each type of UHF antenna, in very brief form. Today's consumer-grade UHF antennas, needed for receiving the great majority of DTV stations OTA in Canada, are divided into two basic designs:
  • Corner Reflector Yagi (pronounced yoggy)
  • Bowtie Reflector
Both have their relative strengths and purposes. The three main antenna manufacturers in the Canadian consumer marketplace (Delhi, Channel Master, and Winegard) make variations on those designs. There were Parabolic models available to consumers many years ago, but that category is now exclusively used by professionals, such as in CATV Head End scenarios or in research.

Corner Reflector Yagis
If you have a clear, direct, unobstructed, line-of-sight aim from your antenna mast to the transmitting antenna and it is within about 80km of it, consider purchasing a corner reflector yagi like a Delhi CYD1470, Channel Master 4248, Televes DAT-75, Winegard PR-9032, or Antennas Direct 91XG (the best of this breed). It is very easy to aim because you can point it like a rifle at the broadcasting site and lock it into place. On a rotor swinging around to several different azimuths it loses out to the other type of antenna because it is so directional (biased in one specific direction) with a fairly narrow receiving aperture and relatively small side lobes, therefore can be quite picky to aim. This is actually a positive feature of the Corner Reflector Yagi because in known areas of signal crowding its great side-rear rejection qualities are needed. Some users do well with long distance reception using a preamp and a fixed mount. Some users do fine with a Yagi on a rotor, but in almost all such rotating situations it is bettered by the other antenna type.
Bowtie Reflectors
If some obstructions such as large trees lay between your antenna, or the broadcast site is more than about 80 km away, or if the stations are at several different azimuths and you want to put an antenna up on a rotor, you require a bowtie reflector such as a Winegard PR-8800, Terrestrial Digital DB-8, or the original Channel Master 4228 (the best of this breed). It's reflector mesh is great at gathering UHF signals that tend to scatter over long distances. Its receiving aperture is very wide and its side lobes are relatively large, meaning that on a rotor it will generally tend to get a digital lock on a DTV station before the Yagis above will. Having said that, it is also fine in suburban situations and in fixed positions for all-purpose situations. Each bowtie (x-shaped signal receptor) is known as a bay, and the greater the range to the station, the greater the number of bays should be. Four-bay versions exist for suburban to fringe use, such as the Delhi 4BT-1483, the Winegard PR-4400, and the new Channel Master 4221HD (the best of this breed). Some bowtie antennas such as the Delhi SL-4BT are sold without reflectors, giving a figure-eight reception pattern to those who are located in between desired stations. The chief difference between a CM4228 and a CM4221HD is that the CM4228 is more directional and provides about 3dB more gain, while the CM4221 has a wider reception pattern.

UPDATE Oct. 31, 2008: Channel Master has stopped making antennas in the USA and moved manufacturing duties to China. They have substantially changed (through outsourcing) all their antenna designs in the process.

UPDATE Jan. 27, 2009: OTA gear suppliers in Canada have run out of stock of the original-style Channel Master 4221s and 4228s. Additionally, testing reveals that the new CM4228HD antennas are weaker in performance than the original CM4228 models. It is advised that if an original CM4228 cannot be purchased, the reader should consider purchasing the next best model shown on the Antenna Chart.

UPDATE Mar. 16, 2009: Ken Nist, of HDTVPrimer.com, has published an easy hardware hack that corrects a significant flaw in the design of the new CM4228HD antenna, improving its performance significantly. Read about it in this thread.

UPDATE May 1, 2009: A thread discusses hardware hacks that consumers can make to improve the performance of their CM4221HD antenna.
Money Is No Object
If you must, and absolutely MUST, have the ultimate in UHF antenna performance, you can buy precision cut single channel or log periodic antennas from professional-grade manufacturers such as Wade or Blonder Tongue, or you can contact Wade about their colossal CATV head end parabolic models. If you think you need one of these bad boys (especially the dual dish model) parked up on your roof, go see a psychiatrist but definitely check your local bylaws and ordinances before you drain thousands of $$$ from your bank account!


Last edited by stampeder; 2014-07-12 at 02:29 PM.
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