HDTV Off Air Antenna Reception - Antenna Selection Discussion

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AntennaWeb is a site that will help you select an antenna for your area.  

VHF Channels 2-13 are broadcast using the Frequency bands from 54MHz to 216MHz.
The big part of the antenna is required to receive these channels.

UHF Channel 14- 69 are broadcast using the Frequency bands from 470MHz to 806MHz (Channel 59 tops out at 746 MHz). The 'pointy nose' part of the antenna shown on this Web page is required to receive these channels.

In general, the closer you are to broadcast antennas, the smaller the house antenna needed to receive a strong signal.  Conversely, the farther you are from the broadcast antenna, the larger the house antenna you will need for a strong signal.  To receive digital broadcasting, signal strength must be "just strong enough," otherwise the entire channel won't be received at all.  Think of it another way -- there is no snowy reception in digital TV -- you either have a strong-enough signal or you don't.  If you don't, then that station won't be received by your HDTV tuner.

For my area in central Connecticut, the following helpful table was generated through AntennaWeb:

The color coding  in the table above represents distances between my home and each TV Station broadcast antenna. Yellow (at the top of the list) represents the nearby stations and violet (at the bottom) represents the stations farthest away.  The compass directions listed are useful when operating your antenna rotator, since they allows you point your antenna right at the broadcast antenna of the station you wish to watch.

Click Antenna Selector, above, to see a larger version of the antenna pie chart (easier to read).

For my area, I also created my own MS Excel spreadsheet to organize information about the area stations I was interested in viewing (see below).  One of the   items I was interested in was the calculated distance from my home to each broadcast antenna for stations I was interested in viewing (See column marked 'Distance (miles)' below.  Of course I substituted a fictitious home address in the table below to protect my privacy, but the point I wish to illustrate is that you will need to determine the approximate map coordinates for you home (Latitude & Longitude) to make these calculations for your home.  I found my house's coordinate location from USGS maps freely viewable on the Web at http://terraserver.homeadvisor.msn.com.  You may navigate to your home by pointing and clicking on either aerial or topographical maps, or by inputting your address.  From the topographical map of your area, you can easily observe the elevation of your home also.

Other Web sites I used to construct my table, below, are as follows:

Convert map coordinates from 'degrees-minutes-seconds' to a decimal value 

Search for HDTV station broadcast applications 

Distance & Bearing from your home to each station (these are true north bearing, so you have to calculate their equivalent compass bearings for your location)

Magnetic declination for any given year and location on the globe from 'GeoMag,' an online Java Program  

Distance between two points (input map coordinates (decimal latitude and longitude coordinates)

Below is a plot plan showing my house in the center where the antenna will be installed and the compass directions pointing towards each TV station broadcast tower for the TV channels in my area.  Click on the plot plan image below to see a larger image.

Lastly, below is a table showing the local stations broadcasting HDTV in my area -- Hartford, Connecticut.

Old NTSC Channel Number

Digital Channel Number Compass Direction Channels Receiving OK at this Antenna Compass Direction Channels NOT  Receiving at this Antenna Compass Direction
3 33 (CBS, Hartford, 33-1) 291 or 288 degrees 3, 20 8, 59
8, 59 10 (ABC, New Haven, 8-1, 8-2, 8-3) and 

59 (UPN, New Haven, 59-1)

233 degrees 3, 8, 20, 59 3 (sometimes)
20 12 (WB, Waterbury, 20-1) 248 degrees 3, 20, 59 8
24, 30 35 (NBC, New Britain, 35-1),

32 (PBS, Hartford, 32-1)

267 3, 20, 59 8, 30(live 5/1/03), 24(live 5/1/03)
61 31 (FOX, 31-1) 268 3, 20, 59 61(live 11/1/2003), 8

Jim