No Such Thing As an HDTV Antenna!

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No Such Thing As an HDTV Antenna!

Article by Eightminute

Over-the-air (OTA) HDTV becomes increasingly more popular. For someone who is employed to noisy analog TV pictures, it is difficult to believe how remarkable a top quality of HDTV broadcasts may be. In fact, HDTV channels received over the air free of charge typically have much better top quality than the same channels received through a paid satellite HDTV subscription. All you’ll want to take pleasure in OTA HDTV is really a HD television with a built-in HDTV tuner and an HDTV antenna.

Huh? Which kind of antenna?! In case you have Ph.D in Electrical Engineering and have never heard about the antenna sort called “HDTV antenna”, it is not since you had been a poor student. HDTV antenna has nothing to do with physics and engineering. It was invented in advertising departments. Marketing found an effective trick to boost TV antenna sales. HDTV is a hot factor these days. Call essentially the same device HDTV antenna, and it sells much better. It makes people to believe they ought to acquire an HDTV model or HDTV optimized antenna to watch HDTV broadcasts. This is very far from truth.

HDTV antenna hype created a massive misconception with regard to TV antennas used for HDTV reception. This article is an attempt to clarify this issue.

Do you know what a regular antenna is? Antenna is really a piece of metal designed to resonate at a particular frequency and to be responsive over a certain range of frequencies. TV antennas are designed to work either in the range of Ultra High Frequencies (UHF), Extremely High Frequencies (VHF) or both. Any station transmitting inside the VHF/UHF frequency bands, could be picked up by a VHF/UHF antenna and transferred to the TV set.

All television broadcasts, digital and analog, are in the VHF and UHF bands. Over 90% of the HDTV broadcasts are inside the UHF, and much less than 10% inside the VHF band. What is crucial from the antenna perspective is that HDTV falls in the bandwidth of a regular VHF/UHF antenna. Not HDTV antenna, not HDTV optimized antenna, just a regular regular TV antenna. What makes a signal to be HD is its content, the way a signal is modulated, and not the carrier frequency it is transmitted on. On the contrary, the antenna knows nothing about the signal modulation and content. Hence, you don’t want an HDTV antenna to pick up the HD signal. An antenna has completely no thought what the signal resolution is. It could be HDTV, SDTV, NTSC, whatever. It’s the job of a HDTV tuner and HD television set to demodulate the signal and to present the actual content on the screen.

Well, the antenna bandwidth and frequency response aren’t the only parameters which are essential for clear TV reception. An antenna has other critical electrical and spatial properties, including antenna gain (directivity) and high front-to-back (F/B) ratio. One might assume that an HDTV antenna should be far more powerful in terms of F/B and gain parameters. Does HDTV reception impose more stringent requirements on antenna gain and F/B ratio?

There is a wrong, yet widespread belief that you require far more antenna gain to obtain digital television. I don’t know where the hell this belief comes from, trigger the situation is exactly the opposite. HDTV has much better noise and interference immunity than the analog television and can produce high top quality video at considerably lower signal-to-noise ratios.

Another crucial specification, F/B ratio, has to do with the antenna ability to cope with a multi-path signal propagation from the towers to the receiving antenna. The higher F/B ratio is, the much better is multi-path rejection (also known as ghost suppression). Without going into technical details, we must say that HDTV signal is a bit more sensitive to multi-path trigger it has slightly larger bandwidth. Multi-path causes dips in the signal spectrum, whereas we need to maintain the spectrum as flat as possible. When signal content is spread over a larger portion of spectrum it is far more likely to be distorted by multi-path. Essentially, what TV equipment manufacturers are trying to do inside the so known as HDTV optimization would be to keep the spectrum flat inside the entire frequency band. It’s crucial for HDTV antenna to have a high F/B ratio in some areas where ghosts could be a dilemma. The point is, however, that most directional, old fashioned and cheap TV antennas have F/B ratio excellent enough to deal with multi-path propagation of HDTV signal and keep spectrum distortion at minimum. If an antenna can deal with an analog signal, it can deal with a digital signal too.

Antennas

Intended for people at great distances from the transmitters, the DB8 is our most powerful multi-directional HD antenna. In fact, its 15.8 dB gain make it one of the most powerful multi-directional antennas available. The bow tie design of the DB8 uses triangular elements instead of rods to greatly increase the bandwidth allowing it to cover the entire UHF band. Additionally, the mesh reflector of the bowtie is more efficient than a rod reflector, is lower in weight, and provides less wind

Antennas Direct DB8 Multidirectional HDTV Antenna

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Antennas question by VegieRedhead: How can I connect 2 tv antennas to same tv?
I live in a rural area, am 30-40 miles from most of the stations, and cannot get all the free stations that I should, even with digital tv. I have one antenna hooked up (have tried different kinds, they all seem to be equally bad) and am wondering if I can hook two antennas to the same tv to improve my reception. Any suggestions?
also – i can get some local channels only on analog (snowy) and the other few only on digital. have to keep switching back and forth. and sometimes lose digital signal altogether, especially during day.

Antennas best answer:

Answer by gilphilloz
Not a good idea. What you need to do is to install a high gain single antenna with a high gain preamp on the roof of your home as high as possible pointed in the direction of the TV station transmitters. You should be looking at a UHF antenna for the new DTV converter boxes which will take effect on June 12th. I would suggest a Channel Master 8 Bay Bow Tie antenna with the Channel Master preamp. See links below.