Digital TV
Sun Nov 8 17:36:07 EST 2009

In a message dated 11/8/2009 12:01:24 P.M. Eastern Standard Time, 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 
Mike Hemeon

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