HDTV OTA Reception

Some Guidelines to improve Reception Qualityantenna which can receive signals only from one
To receive HD signals via satellite or cable might bedirection and is shielded from signals coming from
the best choice as far as image quality is concernedother directions. The antenna has to point in the
but there are thousands of possible individualdirection of the next transmitter. If different channels
situations where OTA (Over the Air) would be thebroadcast from different transmitters your antenna
only option. In this case you would need an OTAmust be equipped with a motor to rotate it in
antenna to receive RF signals in HD format whichanother direction if you change channels.
come from an earthbound station and areIf you have a nice big antenna and it's position the
transmitted through the atmosphere.roof or balcony is relatively unobstructed, yet have a
If this applies to you there are some rough guidelinesweak signal you can employ an amplifier. But make
which will help to make the best out of your OTAsure you really need it. If you receive an already
set up. But be aware that every location has it's ownstrong signal and it is still passed through an amplifier
issues. Settings which work splendidly in Chicago,your TV image might become distorted. If you live
Illinois might not work at all in Phoenix, Arizona, not toclose to a transmitter station an amplifier is most
talk about Quicksand, Kentucky. So if you adhered toprobably not necessary.
all the following suggestions and still can't receiveThere are different technical specifications to an
OTA HD signals or only in bad quality ask for help in aamplifier which might be confusing. Most important is
local TV shop or call your local TV station.the amplification factor in db. Note that the db-figures
First and most important: You NEED an antenna andindicate a logarithmic scale. 10 db means the signal is
if you are at all serious about picture quality you need10 x, 20 db means 100 x, 30 db means 1000 x
an OUTDOOR antenna! Unless there is a situationamplification etc. High quality outdoor antennas should
which absolutely makes installing an outdoor antennahave db values of 15 - 20 or even higher.
impossible do not settle for an indoor antenna. And ifThen there is the noise figure. This should be a low
you live more than 70 miles from the nearestnumber. If you compare different amplifiers brands,
transmitter an outdoor antenna is your only chancethe one with the lower noise figure is of higher
to receive a signal at all.quality.
Unlike waves in the visible spectrum radio waves doThe distortion figure indicates how much the signal
penetrate barriers but there is a considerable loss incharacter is changed by the amplification process.
signal strength. The clearer the signal comes throughThe less the better, of course.
to your antenna the better your reception will be.More advanced (and expensive) amplifiers even
The same principle applies when it comes to thecompensate for the technical fact that a signal of
height in which you place your antenna. If you wouldhigher frequency loses more of it's strength when
perform a test you would recognize that your imagepassing through a coax cable than one of lower
quality improves when you place your antenna higher.frequency. This effect is is made up for by a higher
The reason is that the wave has to go through lessboost of higher frequencies.
and less barriers travelling from the transmitter toIf there is absolutely no way how you could mount
your antenna. On lower levels it might get obstructedan outdoor antenna you'll have to fall back on an
by houses, trees, lampposts etc.INDOOR antenna. In this case testing is the best way
Next to it's placement the antenna size is of majorto come to an optimum reception. This would include
importance. The bigger the better. Antennas consisttesting different OTA antenna brands (come to an
of several dipole elements. The distance between theagreement with your retail store that you can take
two poles within one element should ideally be 1/2 ofseveral antennas home to test. Then buy the model
the signals wavelength. Channel 2 e.g. transmits on awhich delivers the best picture and return the others)
6 m wavelength which requires your antenna toand different positions in the house. A possibility of
measure at least 3 m in diameter. TV antennasplacing it in the attic would definitely increase your
contain several dipole elements with varying length tochances of a good reception, even if it would require
cover the whole range of broadcasted wavelengths.longer cable connections to your TV room. Also try
Secondary Signals might pose a serious problem to adifferent positions within the room. Put it somewhere
perfect reception of your HD signal. These comeaway from the TV set, computers or other digital
about by the wave being reflected by objects nearprocessors otherwise it might come to interference
the antenna. These reflections arrive at the antennadistortions.
with a phase shift compared to the directly receivedIf all fails, even after you have checked for local
signal which can lead to interferences with seriousspecialities, you still have cable and/or satellite dishes
distortions of your TV image. If secondary signals areas alternatives.
a problem in your area you might need a directional