Sunday, October 27, 2013
A recent email
exchange with a reader prompts this week’s essay. It seems she had recently purchased a new HDTV and was having trouble receiving local Channel
12, the CBS affiliate in Cincinnati . The reader, like many people,
has decided that she does not want to pay for cable or a satellite service and
instead would rely on free over-the-air broadcasts. She noted in her email that she could receive
18 other channels just fine.
When she questioned
the salesperson at Best Buy about her problem he responded that it had to do
with the Channel 12 tower location and how HDTV works.
Well, he was close but … no cigar.
For sure, tower location can cause reception issues but in Cincinnati the transmitting towers for all but one TV
station are located within a mile of each other. She was getting all the other stations. So
tower location is most likely not an issue.
The real reason that
Channel 12 is more difficult to receive than any of the other local TV stations
lies in the fact that it is the only channel to use the VHF TV Band. Many will remember the old days when you had
VHF and UHF stations. The major network
stations in Cincinnati were in the VHF band, i.e., 5, 9 and 12. Public TV and FOX were in the UHF band. In fact, all stations still brand themselves
with those old channel numbers but few actually use those channels. In reality Channel 12 is the only station
still using a “real” VHF channel.
Unlike the old analog
transmissions, digital signals and the VHF band just don’t play well
together. The VHF signal does not cut
through obstructions like walls and leaves on the trees as well as transmission
in the UHF band. You might remember that
Channel 9 in Cincinnati had a similar issue when it first began
digital broadcasting. The station solved
the problem by asking the FCC for a UHF channel in place of the assigned VHF
channel. They now use UHF Channel
22. Of course, this change cost lots of
money as it required a new antenna and extensive transmitter modifications. But it solved the problem.
Channel 12 has not
been able or has not tried to get a new channel assignment in the UHF band and
as such that channel remains very hard to receive in many areas of our
community. Perhaps the management of Channel 12 feels that since most local
viewers rely on a cable or a satellite provider for receiving the local
channels that making expensive changes for a relatively small number of people
receiving over-the-air is just not worth it.
There are some things
you can do that can help. For example,
using a high gain amplified antenna will often solve the problem and, of
course, adding an outside antenna is always a good option, albeit somewhat
pricey.
As they say, “the
problem is not in your set.” The problem
lies in the laws of physics and we are not going to be able to change them
anytime soon.
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