Digital TV
TVNETDUDE@aol.com
TVNETDUDE@aol.com
Sun Nov 8 17:36:07 EST 2009
In a message dated 11/8/2009 12:01:24 P.M. Eastern Standard Time,
boston-radio-interest-request@tsornin.BostonRadio.org writes:
>>>Just why was this supposed to be an improvement?<<<
Don't get me started on that. The reason we use the modified-kluged method
of the 1949 analog version of vestigial sideband modulation (8-VSB) is
because the patent for it was owned by Zenith. In the 80's, when HDTV was first
hatched, Zenith still made TV's and they were made in the US. It was
supposed to rejuvenate the TV industry by selling receivers and the first shot
at HDTV was analog!
When digital came along they naturally had to move in that direction and
that added to the delay. Long story short, Zenith was sold to the Koreans
and by the time receivers were being marketed and sold with 8-VSB technology.
Keep in mind at the time of testing in Washington at WRC, all of the
problems that are being experienced now were known back in the early 90's (well
all except the VHF transmission problems).
The TV Networks were actually leading the way for a conversion to COFDM.
There was actually a showdown at The Rayburn Office building with 8-VSB and
COFDM ( the method everyone else uses) and they still went with the 8-VSB
standard. COFDM is a much, much more robust system. It, or a variation of
it, is used for mobile and portable TV everywhere just about everywhere else
but here, Canada, Korea, and Mexico.
Was this a coincidence that 8-VSB was approved or was it just genius on
the part of the CEA? Get an inferior system in place and then take it off the
air and sell the spectrum. Oh, and don't forget the money we spent on
converter boxes for everyone!
In all fairness, the TV stations were supposed to stay on their VHF
channels and the UHF spectrum WAS supposed to be auctioned off for wireless.
Think what the antenna length on a cell phone would look like on a VHF TV
frequency?
Mike Hemeon
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