[QCWA] Digital TV

[Glenn Little WB4UIV]

It has not been determined yet as to the use of channels 2-6. Some 
think these channels will go to the military.

Digital signals should be much less immune to interference. With 
analog you will see the disturbance in the picture. With digital, you 
have to get all the bits and put then together in the correct order. 
With out every last bit, you cannot decode the picture or audio.

There is a test market in North Carolina where all the analog 
transmitters, with the exception of one, will go off the air in 
September. In February all the full power TV stations are required to 
go dark. The low power stations are not currently required to go digital.

You should be able to receive the digital stations on a good UHF 
yagi. You need to eliminate all the preamps as they can distort the 
digital signal to the point of no decode. You need to use good 
quality coax feedline. twinlead is out.

The converter boxes are now for sale with new ones being added as 
they are accepted. You can apply for two coupons good for $40.00 each 
to buy two converters. The coupons cannot be combined to get $80.00 
off on one converter. The converters that you can use the coupons on 
are listed in the paper work that you get with the coupons.

Most TV stations will probably remain on their UHF digital channel.

I am the chief engineer for WCIV TV. I have to answer questions like 
this all the time. I get questions like - "I cannot receive your 
digital signal with my new converter box, I live about 20 miles from 
your transmitter in a single floor apartment. My rabbit ears got me a 
viewable picture with your analog signal, I just cannot see anything 
on your digital signal." It is hard to explain that they need an 
outside yagi antenna.

If you have any more questions ask.

Hope this helps.

73
Glenn
WB4UIV



At 09:49 PM 6/5/2008, you wrote:
>Has anyone heard the technical details of the upcoming
>switch to Digital TV?  I'm not looking for an
>engineering level treatise on the subject, but I'm
>looking for a little more information than what I see
>in the 30 second announcements that run on the local
>TV.
>
>As a ham I'm wondering about several things such as:
>1)  Will the switch to digital involve stations (at
>least the VHF stations) changing frequency, hopefully
>up into the UHF range?  I've been hoping that the
>change means no more channel 2 adjacent to 6 meters.
>
>2)  Will the digital signals be more immune to TVI
>than the current analog signals?  In a general sense
>that seems to make sense, but I realize that I'm
>speculating there.
>
>I'm also wondering about a couple things simply
>speaking as a TV viewer:
>A)  Will the switch to digital TV be a phased-in thing
>or just a sudden overnight occurrence next February?
>Right now I've got one digital equipped TV attached to
>an outside antenna.  I get all the normal analog
>signals that I've always gotten, but when I enter the
>menu to scan for digital signals, I only get one
>channel, and that one is so weak as to be useless.
>
>B)  If I don't decide to get cable, satellite will my
>present VHF/UHF rooftop antenna probably be adequate
>for local reception or will there be enough of a
>change in frequency (as I asked above) to require
>replacement?
>
>C)  Are the converters for use with an older analog TV
>available on the market yet?  I admit that I haven't
>been shopping and asked about them yet, but I have
>read the sales papers from Best Buy, Circuit City and
>a couple of their competitors, and I haven't seen any
>advertised yet.  They all seem much more interested in
>selling new TV's.
>
>D)  Am I the only one who's frustrated by the lack of
>mid-level technical information about this subject?
>It seems that the only advice I've seen on the local
>media is something like, "Get a digital TV, or cable,
>or satellite, or if you don't, you'll need a
>converter.
>
>I admit that maybe I'm more touchy on this subject
>than others as in the late 1960's and early 1970's I
>made my living in TV repair, but I've since moved on
>and am finding this present situation irritating.
>
>73's,
>Paul
>WD8H
>
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