OTA HDTV Reception Q&A

Updates on the DTV transition and how to receive over-the-air digital television for free.

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Location: Richmond, IL, United States

Hello there! I created this blog to share the information about over-the-air HDTV reception you have been wearily searching the Web or calling technical lines for, whether you have decided for less expensive means to get your favorite TV shows, or still adjusting from the over the air broadcast DTV transition that occurred on June 12, 2009. After working for a leading antenna manufacturer for almost 5 years, during which time I've shared my expertise with those who asked on the phone and by email at work, I decided to do the same in the Blogosphere! Confused about getting your local HD channels? Just click through the archives, some of the most useful information is in the early posts from 2005-06. If you want to get in touch with me with antenna related questions, just leave a comment anywhere on this site.

Wednesday, April 16, 2008

THE CONVERTER BOX AND ANTENNA ISSUE

So maybe you found this page because you need a straight answer to this problem:

I just purchased my DTV converter box after waiting eight long weeks for my coupon, I hook up my off air antenna directly to the RF input, and I am only getting a few channels!! What is going on? I thought all the major stations should be broadcasting digitally by now!!!

Well here is the thing - you may have an over the air antenna but probably for the most part been watching off-the-air analog TV on channels 2, 5, 7, anywhere from 2-13 and the occasional UHF, but most of the shows you watch are on a VHF channel. It may be possible that you live in the "fringe area" which is fairly far away, about 50-60 miles.

The thing is, with the analog signals from the major broadcasters still around until February 2009, the DTV broadcasts have to be transmitted on a different frequency, since the analog signals and DTV signals are not compatible with each other, or else you wouldn't need a DTV converter box in the first place. Many channels with VHF analog broadcasts transmit their DTV channels on a UHF channel; some of them will be reverting their DTV broadcasts to their current analog after February 2009, but others will keep their current frequency.

UHF signals, which are at higher frequencies than VHF, by nature do not travel as well by air as VHF. The UHF signals tend to lose their signal strength faster over the miles; consequently, full-power UHF stations transmit at much higher wattages in order to cover the same viewing area and compete with their VHF counterparts.

So as a result, your antenna may need to be replaced with one with more UHF gain, or simply, a larger antenna with more "UHF Elements", which are parts of the antenna that resonate and receive UHF signals. More gain on an antenna means it is more capable of receiving fairly weak and distant UHF signals.

If you use http://www.antennaweb.org/ for your location (please research this site further for more details on how to use it), the last column in the results, "Frequency Assignment", will mention the actual channel being used for the broadcast; DTV channels are noted with a "*", and those entries with a "Feb 17th 2009 (post-transition)" Live Date entry will be the final DTV channel that will be used when the DTV transition completes. Frequency assignments 14 or higher are on UHF.

The channel results are listed in order of predicted strength, with the strongest station on top, and the weakest ones on the bottom. So, if many DTV entries fall near the bottom, or not even show up, then it is likely a stronger antenna will be needed to get all your station. In rare cases, an amplifier will improve the picture, but understand that the purpose of an amp is to overcome signal loss between the antenna and the tuner, through cable, splitters, diplexers, etc. UHF signals also lose more strength in long cable runs than VHF. But an amp will NOT pull in more signal out of the sky; only a larger antenna can do that.

Also. if it turns out many DTV channels are yellow or green, and not showing up, then these signals are very strong, and likely too strong for the DTV tuner to stream the picture, and the thing to do then, if an amp is used, is to remove the amp, and if there is no amp, you may need an inline attenuator, which you can get for a couple dollars at an electronics store.

Once that is taken care of, you will then be ready to enjoy your favorite channels in digital quality as well as their multicasts. But the best thing to do is get the converter box, connect the current antenna, do the channel scan, and see what you get - try that first, you may be fortunate to get all your channels in DTV the first time. Good luck!

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