Over the Air HDTV – The Free Alternative

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Frustrated with high cost, low quality HDTV? Here's how a simple antenna can lead you to the land of free HD.


May. 09, 2008 — by .(JavaScript must be enabled to view this email address)

Rate increases, HD-Lite, outages – there are plenty of reasons why subscribers get fed up with their HD service providers. What are the alternatives? Switch to another provider? That’s one solution, but it could simply bring its own set of problems unique to that service. There’s always Over-the-Air (OTA) HDTV. Just like your mom and dad (and grandma and grandpa) got their TV for free through the rabbit ears, so can you get your HDTV for free.

OTA HDTV in Brief
Receiving OTA HDTV is in most ways just like receiving the OTA analog signals that have been around since the days of “I Love Lucy.” Broadcast towers transmit a digital signal which is captured by the receiver (antenna), which is sent to the TV (in this case an HDTV, with either a built-in tuner or using a set-top box tuner). The antenna can be of the outdoor or indoor variety, and can include any number of accessories, including a rotor, an amplifier, and other augmenting features. The digital signals can be broadcast as VHF (Very High Frequency) or UHF (Ultra High Frequency). The VHF band covers channels 2-13, and the UHF 14-69. (After the analog to digital transition in February 2009, channels 52-69 will be claimed by the federal government for reallocation elsewhere). Stations broadcasting in digital can choose to broadcast programs in HD, and many do. Just what is broadcast in HD, and when, will vary from station to station. 

One big difference between digital OTA and analog OTA is that with digital there is no in-between – you either get the channel or you don’t. As many analog OTA users will attest, “snowy” pictures can be quite common, caused by a weakened signal due to any number of factors, including distance, geography, and obstructions. The video and audio is coming through, but the picture isn’t the sharpest, though it will do. With digital, it’s an all-or-nothing situation. “We call it the ‘cliff effect,’” says Shermaze Ingram, Senior Director of Media Relations for the DTV Transition Campaign at the National Association of Broadcasters (NAB). The digital receiver (antenna) requires so many bits of data to deliver content to the television. If the signal is weak enough such that the antenna is not receiving the minimum required data, it will simply show nothing at all. According to Ingram, however, “if you are already getting good analog signal, you should be able to get good digital.” 

As the controversy over HD-Lite continues to grow, many consumers point to OTA HDTV as the best source for quality, uncompressed HD. Here are some facts on OTA HDTV that the consumer needs to know. First, OTA HDTV is compressed, using MPEG-2 technology. This compression has to be done in order to comply with regulations that mandate broadcasters to use 19.4 Mbps per channel – no more, no less. However, broadcasters have some freedom to determine how much of the 19.4 Mbps is allocated for an HD program. “One can image a pie just shy of 20 Mbps around,” says Kelly Williams, Senior Director of Engineering for the NAB. “Broadcasters can divvy it up any way they want.” And most do, by multi-casting. That is, they will broadcast more than one program on a channel, creating sub-channels. As an example, in my town of Burlington, Vermont, WCAX (a CBS affiliate) broadcasts their analog signal on channel 3, and their digital content on channel 3.1. At any given time during the day they might also broadcast a different program on channel 3.2, and yet another on sub-channel 3.3. This multi-casting enables broadcasters to feed multiple programs at the same time. This can, and will, include HD content. “A broadcaster can make a nice HD picture and still have room for a couple sub-channels that require a low bit-rate,” says Williams. Where some cable companies have been criticized for sending HD-Lite content that weighs in as low as 9 Mbps to make room for all the other bit-rate-consuming content they promise to consumers, the broadcasters have a little more flexibility. The result tends to be HD content compressed only as much as is necessary to make room for a couple low bit-rate sub-channels, like a weather or radar sub-channel or an SD sub-channel that might only need 1.5 Mbps. The result is usually HD content that is in many cases superior to what subscription television service providers can offer. In fact, it isn’t uncommon to see broadcasters completely drop their sub-channels for the duration of the HD program being transmitted, maximizing the quality of that HD content.

Do Your Research
Before purchasing an antenna (or even deciding to switch to OTA service) the consumer should do some research on what content can be received. This is going to vary widely, depending on one’s location. The distance to any given tower, as well as the terrain between the tower and the receiver, will impact one’s ability to receive OTA HD. Fortunately, the National Association of Broadcasters and the Consumer Electronics Association (CEA)have teamed up to bring us AntennaWeb.org, an extremely helpful resource that informs consumers of local broadcasters. Simply type in one’s address to generate a map which details one’s orientation in relation to nearby broadcasters, as well as the distance to their towers. This helps determine which, if any, stations are likely to come in, as well as the direction the antenna should be facing when installed. Inputting an address will also generate a list of nearby stations, their call-sign, channel, and network affiliate, as well as compass heading and whether they transmit in UHF or VHF. The list of channels accessible is also color-coded: they yellow channels at the top will have the strongest signal relative to your location, and the blue and violet channels at the bottom of the list have the weakest. 

Once a list of available stations has been generated, the consumer can decide which channels he/she wants to receive. The AntennaWeb list designates stations that currently broadcast in digital, and it also indicates which frequency a station will broadcast on after the February, 2009 switch from analog to digital. This is a vital piece of information. Some stations currently broadcast their digital content (including HD) on a UHF channel, but will be switching to VHF after the transition. This will be a determining factor when it comes to choosing an antenna (see below).

Selecting an Antenna
Rule #1 for selecting an antenna: There is no such thing as an “HDTV Antenna.” This is a marketing ploy used by some distributors and manufacturers to fool consumers. So-called “HDTV Antennas” are often designed for indoor use and look very sleek, futuristic, and compact. To receive OTA HDTV, the consumer needs, 1) an HDTV with a built-in tuner (or a set-top box tuner), 2) cable to connect the antenna to the HDTV (most distributers recommend solid copper R6 quad shield coax, and 3) an antenna properly color-coded to receive in-range stations broadcasting in digital. Regarding this last, the general rule is to purchase a combination VHF/UHF antenna. It does not have to be an “HDTV Antenna” or a “Digital Antenna.” Remember: these are marketing terms used to confuse the consumer. In most cases, a combination antenna will bring the best chance of receiving all available digital channels (and their accompanying HD content), particularly once the February, 2009 transition is complete. 

When shopping for an antenna, look for the CEA-certified color-coding mark on the packaging. Match the color-coded label for an antenna with the colored list of accessible channels generated by the AntenaWeb.org list. Again, this will vary for everyone. “There is no one solution,” says Ingram. “As a general rule, the larger the antenna, the better the performance,” says Denny Duplessis, co-founder of Denny’s Antenna Service in Ithaca, Michigan. Unfortunately, those larger antennas are also commonly considered “ugly,” and consumers might shy away from then for aesthetic reasons. Still, Duplessis insists that more compact and attractive antennas can still be found that will adequately perform. “Winegard makes a combination antenna that is narrower and specifically made for high band VHF channels and UHF channels,” says Duplessis. Most markets across the country will have at least one high band VHF channel (7-12), while very few will use the low band VHF channels (2-6). 

When using AntennaWeb.org to determine which antenna to buy, Duplessis advises going with an antenna that’s slightly bigger than you might think you need: “Even if you think a mid-size antenna might do it, it’s worth spending the extra $15 on a bigger antenna, especially if you want to consistently receive channels.” Consumers should note that AntennaWeb.org tends to be conservative when generating a list of available or accessible channels. “They don’t want to tell you that you are going to get channels that you aren’t going to get,” says Duplessis. The result is usually a pleasant surprise: consumers might end up getting additional channels that they didn’t expect to receive, rather than the converse. 

Currently AntennaWeb.org only uses its color-coding system for outdoor antenna recommendation and certification. Additional equipment (like a preamplifier for signal boosting or a rotor for adjusting antenna direction) may be necessary, depending on one’s distance to broadcasting towers and the orientation of those towers. Consumers who are not comfortable installing an outdoor antenna should seek the help of a professional installer. “Contrary to public belief, falling is not the #1 cause of injury in rooftop accidents,” says Duplessis. “It’s the overhead powerlines.” If an individual is inclined to install an antenna, location and awareness of powerlines is the most important safety precaution.


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