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Duane Allen · July 20th 07, 12:58 PM posted to rec.radio.amateur.antenna

Dave Platt wrote:
In article . net,
Duane Allen wrote:

If your using the antenna for HDTV, you need only the UHF elements,
which for many TV antennas are the shorter elements at the front end of
the antenna. The VHF elements will not be needed when all OTA TV
stations go to HDTV.

I believe that this statement is untrue, or is at least of somewhat
limited (regional) truth.

Although most TV stations have chosen to use UHF-band for their
digital signals, that is not universally true. Some stations whose
primary (NTSC analog) transmitters are in the VHF high-band (channels
7 through 13) have decided to use their VHF channels to carry ATSC
digital, after the Big Switchover occurs. In a very few areas of the
country, there's even a station or two which will be using its VHF
low-band frequency slot (channel 2 through 5) for ATSC. The FCC has
recommended against using VHF lowband channel 6 for ATSC, in order to
prevent interference with the bottom of the FM broadcast band.

I believe that these stations are electing VHF for ATSC, rather than
using their "interim" UHF channel assignment, because they'll be able
to get better ATSC signal coverage that way. They can operate at
higher power on the VHF band than they could on UHF (likely because
their interim UHF frequency assignment has co- or adjacent-channel
users not all that far away).

In most areas of the country, a good UHF antenna will suffice for ATSC
digital. In a few (e.g. SF bay area) you'll still need to have an
antenna capable of both UHF, and VHF high-band, to get all of the
local stations... and in one or two areas you'll still need a
full-range VHF-lowband/VHF-highband/UHF antenna such as is used today.
Some people who have bought "digital TV" or "HDTV" antennas (UHF-only)
are likely to be annoyed, when they lose a channel or two on The Big
Day.

A nationwide table of the ATSC frequency assignments can be found at

http://hraunfoss.fcc.gov/edocs_publi...C-06-150A1.pdf

Thanks for taking the time to correct my error.