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Discussion Starter · #1 ·
I wonder if someone could clarify what the plan is for the frequency use after 2006. For example if a VHF channel moves to a UHF channel for the transition, what happens to that channel after the transition, does it stay at it's new UHF home and the gov auctions off the old VHF space, or after NTSC gets shut off (if it ever happens), does it move back to it's old VHF home and the gov auctions off the UHF space. The reason I'm asking this is that all my locals (within 80 miles) are going to be on UHF primarily 30 and above, so I'm thinking a better UHF head is in order, and leave the old VHF head as is, if however they're going to switch back after the changeover, then I would replace my aging VHF head with something newer. Any insights anyone???
 

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The original plan was to move all the stations to UHF. Now the plan is to give broadcasters the choice of their NTSC channel assignment or the DTV transition channel. Somewhere I read that VHF high band (7-13) is being retained, but VHF low band (2-6) was going to be auctioned off.


The FCC is auctioning off UHF channels 60-69. They just approved a deal that will allow NTSC channels in that band to move to a lower-frequency DTV transition channel, but broadcast NTSC instead of DTV on that lower channel until 2005. I think the following phase of the UHF auction involves channels 52(?)-59. We’re able to get the same number of TV channels in less bandwidth because the near channel and 7th/14th channel limitations of NTSC go away.


VHF transmissions typically require smaller amounts of power than UHF to achieve the same effect area of coverage. At the same time, longer wavelengths (lower channel numbers) require larger antennas. This means that these long-range VHF broadcasts aren't as attractive to wireless data and telecom companies. At the same time, DTV broadcasts require significantly less power (wattage) to achieve the same coverage as NTSC broadcasts.


Personally, I would be delighted if the transition got rid of VHF entirely for OTA television. Low band VHF is subject to nasty impulse noise interference. UHF antennas are far smaller and less objectionable for installation and aesthetics. Europe gets by quite nicely with satellite dishes and UHF only terrestrial antennas.


Jim in Shreveport

*Interesting footnote: Channel 37 isn't used for television because it includes the resonant frequency for Hydrogen. It is kept "quiet" for radio astronomy purposes.


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Let me get this straight, this show is hi-def and 5.1, but my local affiliate makes it crappy NTSC and mono?!
 

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Some NTSC Vs with ATSC U assignments MAY move their ATSC back to the old VHF channel after NTSC goes away. It depends on interference issues as well as what the station would prefer. There are HUGE differences in electricity costs for operating in V or U, U always requiring lots more than V for comparable coverage. I'd suggest asking your local stations what they think will happen. But realistically, you'll probably need to replace your antenna anyway before NTSC goes away! http://www.avsforum.com/ubb/wink.gif


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HiDefDave
 

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Discussion Starter · #4 ·
Thanks for the answers guys.
 

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Scooper,


I'm definately not 100% certain that any VHF spectrum is going away. I just heard that originally Congress wanted to sell it all off and some people are still eyeing low band VHF.


Auctioning off UHF channels in the 50's and 60's seems like a definate goal right now. There used to be UHF channels 70-89. While they weren't widely used, there were (and still are?) translators is the rural western US. These frequencies were auctioned off for our early analog cell phones. Heck, the FCC compromised the DTV go-live date of May 1st, 2002 just to convince PAX, Pappas Broadcasting and a few others ne'erdowells to vacate the spectrum.


Jim


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Let me get this straight, this show is hi-def and 5.1, but my local affiliate makes it crappy NTSC and mono?!
 

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The original plan was for the TV channels above 51 to be reallocated for other services, once the transition from analog to DTV was complete. Originally, all low and high VHF stations were to migrate to UHF assignments.


However, some high V's and even a few low V's now want to keep their channels, and NOT move to UHF. In Philadelphia, WHYY broadcasts on analog channel 12, and they are planning to keep that channel once the transition is complete, instead of staying on UHF-55 for digital.


The problem with low V's (2-6) is interference due to atmospheric signal propagation enhancement, otherwise known as 'skip'. Reliable DTV reception on 2-6 will be a mess when 'skip'occurs. With analog signals, two stations can 'beat'against each other and cause all kinds of interference.


However, digital signals fighting 'skip'may never lock up at all on your set-top box. This phenomena has also been observed on high V's, and there is even atmospheric enhancement of UHF channels (typically, tropospoheric ducting) from time to time.


The channels 60-69 were supposed to be auctioned off first, followed by 52-59. This may take some time. Some of the DTV stations on channels in this range may opt to keep an old VHF allocation.


The plans of the FCC wil inevitably go awry when politics are involved.


KC
 

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Jimbo - your observations on lower VHF might be generally true, but my local broadcasters on 4 and 5 (NTSC) seem to have no problem with it - channel 4 is local PBS and channel 5 is WRAL - WRAL argueably has the best NTSC picture in the area !


Some of the information I've heard on which channel goes back really seems to "screw" my local stations -


NTSC DTV

4.....59 (not on air yet) PBS

5.....53 WRAL (CBS)

11....52 WTVD (ABC)

17....55 WNCN (NBC)

22....57 (not on air yet) WLFL (WB)

28....27 (not on air yet) WRDC (UPN)

30....42? (not on air yet) SAH

36....?? (not on air yet PBS

40....38 (not on air yet) Independent

47....15 (not on air yet) WRPX (PAX)

50....49 WRAZ (FOX)


So it looks to me like some of these get the shaft from both upper UHF going away and lower VHF going away !


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You CAN put antennas on your owned and/or controlled property...

http://www.fcc.gov/csb/facts/otard.html
 
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