1/9/08
Erecting a TV Antenna
If you have been told that you may not
erect a small outdoor TV antenna, that is probably
wrong. The Telecommunications Act of
1996 has a provision that preempts (overrules) nearly all local restrictions such
as deed restrictions, home-owners association rules, renters
contracts, and so on. For more details
see FCC Fact Sheet.
Late
news: The determination of permanent DTV
channel numbers is complete. The results
are at DTV
Final Channel Designations. There
you will find a list of stations for your city.
For each station, the current NTSC channel number is shown, followed by
the permanent DTV channel number after 2009.
The
permanent change takes place on February 17, 2009. At that time channels 52-69 will be vacated
and reallocated to other uses. Only 37
stations have elected to stay in channels 2-6.
You must
consider 02/17/09 when planning an antenna system. Many of your stations will move on that
date. Today your DTV stations are
probably all UHF. But on 02/17/09 many
DTV stations will move to VHF. The
VHF-high channels (7-13) are probably the best channels for DTV since VHF-low
has interference problems and UHF has tree and valley problems.
Note also that now is not a good time to buy a Yagi antenna. Present Yagi antennas are optimized for
channel 69. But beginning on 2/17/09, 51
will be the highest channel, and a new generation of Yagi antennas cut for
channel 51 will be the most desirable.
For the next few years Yagi buyers must pay close attention to the
frequency specs.
Many people
live in areas where TV signals are strong.
Even if these people know nothing about selecting or installing an
antenna, they will probably succeed anyway.
This website is written mainly for people in areas where reception is
nontrivial to very difficult. A trip to
the website www.antennaweb.org will
tell you quickly into which group you fall.
If your must-have stations are in the yellow or olive-green range then
there is not much reason to study anything.
(But if your present antenna is disappointing then read on.)
If you are
not a do-it-yourself type, you can find an installer in the Yellow Pages under
“Antennas” (or possibly “Televisions – Dealers & Services”). The total cost (parts and labor) will range
from $100 for an easy install to $800 for a difficult install, with $300 being
the most typical bill. If you do it
yourself, you will pay almost $200 just for the hardware. (Antenna: $70, amplifier: $70, 50 feet of
RG-6: $30) You might be able to get some
free advice or a free rough estimate over the phone or by visiting the installer’s
shop. If he comes to your home, the
estimate will not be free but it will be accurate.
There is a
chance that the first antenna you install will not meet your expectations. Once an outdoor antenna has been installed,
the seller will rarely take it back.
Even Radio Shack will not take back an installed outdoor antenna. The cost of a second antenna might wipe out
any savings you hoped for by doing it yourself.
An installer will never charge you for two antennas if he is wrong on
the first try. Generally, indoor
antennas can be returned if in the original packaging.
Proceed at your own risk:
·
Every
year people get killed while erecting antennas.
·
There
are places within the station’s broadcast radius where reception is not
possible.
·
There
are places where reception is so difficult that the challenge might outwit the
installer.
·
Although
the dollar cost of an antenna system is modest, a lot of your time might be
required.
The author
will not accept responsibility for any unexpected losses.
The following
antenna sections, like the rest of the primer, assume only a high school education. But you will find them to be slightly more
technically challenging.
Antenna Issues:
Antenna Projects -- For Do-It-Yourselfers in very weak signal
areas
Encyclopedia of TV Antenna Terms
and Topics
(including satellite dishes)
Antenna
aperture (capture area)
Broadside antennas (see Stacked
antennas)
CATV/MATV (Community
Antenna TV, Municipal Antenna TV)
Characteristic
impedance (see
Impedance)
Circular polarization (see
Polarization)
Collinear antennas (see Stacked
antennas)
Combiners (see
Splitters/Combiners/Diplexers)
Combo antennas
(for VHF and UHF)
Corner reflector (see
Reflector antenna
DBS (Direct
Broadcast Satellites)
Diffraction
(The bending of radio waves)
Diplexer (see
Splitters/Combiners/Diplexers)
Disk antennas (see omni-directional antenna)
Distribution
amplifier (see Antenna
amplifiers)
Driven elements (see Yagi
antennas)
DSS (DBS
Subscription Service)
(see DBS)
EMI
(Electromagnetic Interference) (see Interference)
Ganged antennas (see Stacked
antennas)
Ghosts (see
Multi-path interference)
Ground plane antennas (see
Vertical antennas)
Inductors
(coils and transformers)
Log-Periodic
antenna (Log Periodic Dipole Array, LPDA)
LPVA
(Log-Periodic V-Array)
(see Log-Periodic antenna)
LNB (Low Noise
Block-converter), LNBF
Matching transformer (see
balun)
Mismatch
between antenna and feedline
Multi-switches
for DBS systems
Noise/Noise
figure/Noise factor
Parabolic antenna (see Reflector
antenna)
Parabolic dish antenna (see Dish
antennas)
Power Injector (see antenna
amplifiers)
Preamplifier (see
antenna amplifiers)
RFI
(Radio Frequency Interference) (see interference)
Rotors (antenna
rotators, motorized antenna aimers)
Stores and
websites supplying antenna equipment
Twin-lead
transmission line (ribbon cable)
This page is part of “An HDTV Primer”, which
starts at www.hdtvprimer.com