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The official final DTV Table Of Allotments/channel change thread - Page 240

post #7171 of 7384
I've been doing this radio and TV stuff for over 40 years and I've heard a lot of myths and misinformation over the years.

The most popular myth these days is that rain attenuates VHF/UHF signals. It does not. This myth seems to have come about because of the well known rain fade affect on satellite TV signals. Rain fade occurs when the size of the raindrops becomes a significant percentage of a 1/4 wavelength of the frequency. This starts to occur more frequently around 10 GHz. Raindrops cannot reach the size of a 1/4 wave on UHF.

Anyone who has signals that disappear when it rains is just unaware that they're relying on some amount of atmospheric bending of the signals to receive them in the first place.

Temperature inversions are what bends the signals. It doesn't take a very strong inversion to have some affect. Just the normal day/night cycle is enough to bring in a station that needs a little help. Solar heating tends to break up the inversions in the daytime, especially in the afternoon, which is why so many people complain about poor reception in the afternoon. Around sunset inversions reform as the atmosphere stabilizes and many report better reception.

Each situation is different though and the exact location of the transmitter, your location, the elevations at each end, and what's in between make a lot of difference. These factors can account for nearly all of the vast array of experiences that people have with reception.

I can receive stations from more than 10 different transmitter sites so there isn't much I haven't experienced here. Compared to most people's experiences with DTV reception, I have the opposite experience with my local stations. My local antenna farm is Walnut Grove which is 54 miles away over a 2 edge path. Those antennas are about 2000' above sea level. My antennas are 2650' above sea level. Not many people live at a higher altitude than the transmitters. My best reception is in the afternoon with no inversions and can be quite poor on some nights depending on the height of the inversions.

A typical evening cycle here is good reception in the late afternoon, then a decrease in the signals around and after sunset, and then a return to normal later in the evening. I believe what is happening here is that an inversion forms below me but above the transmit antennas causing the signals to be bent down thus decreasing my signal strength. Later on the inversion lowers below the transmit antennas, there is no bending, and the signals return to daytime levels.

As to the affect of inversions on VHF versus UHF, from what I've read and what I've experienced would indicate that UHF is affected more, and I understand microwaves are affected even more. This is not to say that high VHF is unaffected. I've seen 30 db increases on high VHF on some paths but 40 dB increases on UHF on the same path. I've seen some pretty dramatic increases even on channel 2.

The issue of tropospheric ducting and the affects of temperature inversions is a little more confusing since people mean different things when they talk about this. Often tropospheric ducting is used to describe the more typical extended bending of a signal that allows it to be received a couple hundred miles away. Other times it means an actual duct in the atmosphere where a signal is trapped between 2 layers in the atmosphere and can be propagated for thousands of miles like the one that occurs between the west coast and Hawaii in the summer. Stations at each end of the duct have to be at the right altitude to get signals in and out of the duct. I suspect that most of what we experience with DTV is just signal bending to extend the range and not true ducting.

Yesterday morning I experienced an unusual path to the south. I received strong signals from KEYT and KPMR from Broadcast Peak north of Santa Barbara which is 257 miles from here and my most distant DTV reception. KEYT had to override KEXT-CA analog on 27 and KPMR had to override KMAX on 21 which is a local 1 MW station.

Chuck
post #7172 of 7384
Tropospheric refractive indices are higher for UHF than VHF (and so are the free-space and real-world signal losses). At the longer wavelengths of VHF true ducting becomes a rare event - I can count on my fingers the number of times that I got it on low-VHF from Florida vs scores of events on UHF NTSC. See http://www.qsl.net/wa5iyx/WESH-2.htm and http://www.qsl.net/wa5iyx/UHFTVDX.htm as an example. I used to think that our trans-Gulf ducting went away in the daytime due to each end burning off over land, but now it appears that it's more likely that it just elevates during the day.

BTW, the first 1000-mi + DTV tropo logging seems to have been made this past May with a Melbourne, FL Ch 43 into Massachusetts. My best DTV tropo is still 995-mi Tampa http://www.youtube.com/watch?v=nsOTvYVXY-M
post #7173 of 7384
I've heard about the over the gulf duct. I think there's a similar one that forms over southern Australia. I'm sure you'll never hear of 1000 mile ducts on the west coast. Terrain gets in the way.

Chuck
post #7174 of 7384
Trop affects UHF more easily than VHF, but it is often great on VHF-high as well. Some of the appeal of UHF trop in the analog days may have been from the facts that the UHF band was less congested and UHF antennas more directional.

On very rare occasions, I've had trop on VHF without any trop on UHF (Little Rock opening of 2006) - even a couple events of lowband-only trop.
post #7175 of 7384
Let's try this again (if my SWBell/AT&T DSL doesn't keep dropping out ...)

Local vegetation can be a large factor. My UHF became more problematic after the trees grew large here (new development c. 1971) after the 1980s. My 20' AGL 8-bay bow-tie UHF (now a CM-4228) still has a good shot east (along the apexes of the other houses rooftops), but there are more-distant terrain issues http://www.qsl.net/wa5iyx/myhorizon.htm at those azimuths to deal with.

I'm always hoping that a 144-MHz Es event will link into that Hawaiian duct, but the great-circle path from here is across Mexico and off the coast - so it could there without a hint FM stations have been logged via ducting on the Big Island from coastal (southern) California and over to the (mainland - not just Baja) west coast of Mexico.
post #7176 of 7384
*oops*
post #7177 of 7384
AMENDMENT OF SECTION 73.622(I), POST-TRANSITION TABLE OF DTV ALLOTMENTS, TELEVISION BROADCAST STATIONS (PANAMA CITY, FLORIDA). Issued a Substitution of channel 18 for channel 7 at Panama City, Florida for station WJHG-TV. (Dkt No. 11-140 RM-11683 ). Action by: Chief, Video Division, Media Bureau. Adopted: 10/18/2011 by R&O. (DA No. 11-1735).

http://transition.fcc.gov/Daily_Rele...-11-1735A1.pdf
post #7178 of 7384
Speaking of channel changes, yesterday's FCC daily digest included a voluntary transfer of control grant to Nexstar for transferring control in Evansville, Indiana of WTVW, channel 28 from Nexstar to Mission Broadcasting and transfer of control of WEHT, channel 7 from Gilmore to Nexstar.

Effectively Nexstar traded a "more desirable" channel 28 for a "less desirable" channel 7.

Why would they do that???
post #7179 of 7384
Given that Mission is a shell corporation for Nexstar to illegally own two stations in a market, they didn't trade it away but rather they now control both.

- Trip
post #7180 of 7384
Aha. Now I understand... Thanks, as always, for the clarification Trip.
post #7181 of 7384
Quote:
Originally Posted by Trip in VA View Post

Given that Mission is a shell corporation for Nexstar to illegally own two stations in a market, they didn't trade it away but rather they now control both.

- Trip

Just like in Terre Haute, IN, Nexstar owns WTWO (NBC) & shell company Mission Broadcasting owns WAWV (ABC). Terre Haute only has 3 commercial licenses to the market, & this is a duopoly that needs to be broken up. If the FCC knew about Nexstar owning Mission Broadcasting, then how did they allow a duopoly like this? The FCC has been questioning Granite Broadcasting & their shell company, Malara with owning WPTA (ABC/CW) as Malara & WISE-TV (NBC/Fox/MNT) as Granite in Fort Wayne, IN & KDLH (CBS/CW+) by Malara & KBJR-TV (NBC/MNT) by Granite in the Duluth, MN market.
post #7182 of 7384
Why would the FCC care? They're too busy planning the extinction of broadcast television to worry about who's going to control those licenses for the final few years.


Sarcasm off.
post #7183 of 7384
Quote:
Originally Posted by Trip in VA View Post

Given that Mission is a shell corporation for Nexstar to illegally own two stations in a market, they didn't trade it away but rather they now control both.

- Trip

Sinclair owns WNAB( CW ), WZTV( FOX ) and WUXP( MyNetwork ) in Nashville.
post #7184 of 7384
Sinclair has agreed to buy the Freedom Broadcasting group of stations, including our own KFDM here in Beaumont, Texas for $385 million. This will also give them a duopoly in West Palm Beach, Florida.
post #7185 of 7384
Looks like Mission Broadcasting is now HQed in Westlake, OH (Cleveland suburb):

http://biz.yahoo.com/ic/119/119426.html

They were in another Cleveland suburb, Brecksville, and started life in the spare room of a house in Sharon Center, OH, about a 2 minute drive from where I used to live. The local paper did a profile of them, which is the only reason I know that ("Major TV company in guy's spare room").

They own no stations here, though the link above indicates that former Cleveland TV executive Dennis Thatcher is now their COO.
post #7186 of 7384
AMENDMENT OF SECTION 73.622(I), POST-TRANSITION TABLE OF DTV ALLOTMENTS, TELEVISION BROADCAST STATIONS, MONTGOMERY, ALABAMA. [WNCF] Substitution of channel 31 for channel 32 at Montgomery. (Dkt No. 11-137 RM-11637 ). Action by: Chief, Video Division, Media Bureau. Adopted: 11/04/2011 by R&O. (DA No. 11-1863).

http://hraunfoss.fcc.gov/edocs_publi...-11-1863A1.pdf
post #7187 of 7384
WLJC-7 wants 185 kW. Good luck with that one.

- Trip
post #7188 of 7384
I'd like to see their justification for asking for more power than a high-VHF station is even permitted...
post #7189 of 7384
They cite 73.622(f)(5), the same rule WBNS cited when they requested 1700 kW. We saw where that one went.

I imagine it will ultimately be amended to 160 kW.

- Trip
post #7190 of 7384
Quote:
Originally Posted by WA5IYX View Post

Let's try this again (if my SWBell/AT&T DSL doesn't keep dropping out ...)

If your area has U Verse (Beaumont-Port Arthur, TX does but its only Internet and they havent rolled out U Verse to every CO yet and they cannot advertise it if its not available in a major % of the area and they have to offer 2 out of 3 features from what I have been told)...and you can check at att.com to see if it IS available (look at Broadband, NOT DSL using your address or phone number), you can get your DSL pricing adjusted..I got my 3MB DSL at $35 kicked up to 6MB and the price knocked DOWN to $24.95 month (the U Verse price) just by calling ATT and saying I wanted the 6MB but didnt want to pay $100 for their "special" modem (DSL II)....sooooo keep that in mind...I just saved a lot of money on my DSL by NOT switching!
post #7191 of 7384
In reviewing a number of recent power increase applications (such as KRIV/Houston's app for 800 kW from 300 kW), Section 73.622(f)(8)(i) is cited as the reason for exceeding ERP caps.

Now that things have really settled down from the transition and this thread can sustain some more activity, how about a "Big Dummy's Guide for Untanging FCC Legal Speak"?

Here are some discussion starters:

1). What's the history behind the largest station exemption? Was there one facility that wanted to exceed the limits that served as the initial test case?

2). How can the largest station be determined without ambiguity? I seem to recall that here in Dallas, WFAA was cited by one applicant and KDFW was used by another applicant.

3). And how the "largest station in the market" determined in first place since it presumably had to exceed the ERP/HAAT caps to attain that lofty status?
post #7192 of 7384
Quote:
Originally Posted by re_nelson View Post


3). And how the "largest station in the market" determined in first place since it presumably had to exceed the ERP/HAAT caps to attain that lofty status?

The largest DTV station in a market is usually a station that began life as a VHF analog station, maximized their DTV facilities, and pushed out the DTV contour the full 5 miles that was allowed. In order to do so, the DTV channel needed to be clear in most directions so that additional interference did not occur.

In spite of the 5 miles extension, most stations found that DTV does not cover as well as analog. In my opinion, the likely reasons are;
1. Viewers often watched analog pictures well below 28 db s/n ratio; the minimum signal strength that was assumed to be adequate.
2. Difficulty optimizing a DTV antenna because the digital signal strength meter in an HDTV is slow to respond and isn't as effective as the obvious visual improvement of an analog picture.
3. Multipath issues that invalidate the predicted s/n values.
post #7193 of 7384
Quote:
Originally Posted by re_nelson View Post

1). What's the history behind the largest station exemption? Was there one facility that wanted to exceed the limits that served as the initial test case?

Remember that the limit on UHF power is actually 365m 1000 kW. With the sliding scale that is in place, this means that without 73.622(f)(5), a 610m high facility would be capped at 316 kW. It wouldn't make sense in the world of digital to artificially limit power based on what a station's analog coverage was. This would be particularly true in places where one of the big four networks was now on UHF for one reason or another.

The transition gave smaller stations the opportunity to increase coverage, and in fact the original table of allotments had floor values that stations' assigned power levels did not go below (1 kW low-VHF, 3.2 kW high-VHF, and 50 kW UHF).

Quote:


2). How can the largest station be determined without ambiguity? I seem to recall that here in Dallas, WFAA was cited by one applicant and KDFW was used by another applicant.

I have a list of stations ranged by largest amount of area covered:

http://www.rabbitears.info/market.ph...est=maxcontour

But I don't think you actually need to use the largest station. As long as you can demonstrate that at least one station in the market is larger than your own, then you would be in the clear regardless.

Quote:


3). And how the "largest station in the market" determined in first place since it presumably had to exceed the ERP/HAAT caps to attain that lofty status?

Tower Guy pretty much got this one. Since 100 kW VHF analog covered more ground than a 5000 kW UHF analog, when the digital assignments were handed out, many of those 100 kW VHFs were granted 1000 kW UHFs (or VHFs exceeding normal power limits) to attempt to replicate analog coverage as well as possible.

Here are the original allotments, courtesy of Doug Lung: http://www.transmitter.com/FCC98315/chanplan.html

- Trip
post #7194 of 7384
AMENDMENT OF SECTION 73.622(I), POST-TRANSITION TABLE OF DTV ALLOTMENTS, TELEVISION BROADCAST STATIONS (LINCOLN, NEBRASKA). Proposed substitution of channel 15 for channel 51 at Lincoln, Nebraska for station KFXL-TV. (Dkt No. 11-192 RM-11646 ). Action by: Chief, Video Division, Media Bureau. Adopted: 11/21/2011 by NPRM. (DA No. 11-1924).

http://transition.fcc.gov/Daily_Rele...-11-1924A1.pdf
post #7195 of 7384
Sitting on the various petitions to move from VHF to UHF, but jumps to make the wireless companies happy within a week.

- Trip
post #7196 of 7384
A little love now, a large paycheck later. See also Meredith Attwell Baker. Why should bribes only be for elected officials?
post #7197 of 7384
Quote:
Originally Posted by Falcon_77 View Post

AMENDMENT OF SECTION 73.622(I), POST-TRANSITION TABLE OF DTV ALLOTMENTS, TELEVISION BROADCAST STATIONS (LINCOLN, NEBRASKA). Proposed substitution of channel 15 for channel 51 at Lincoln, Nebraska for station KFXL-TV. (Dkt No. 11-192 RM-11646 ). Action by: Chief, Video Division, Media Bureau. Adopted: 11/21/2011 by NPRM. (DA No. 11-1924).

http://transition.fcc.gov/Daily_Rele...-11-1924A1.pdf

Isn't the FCC trying to get stations OFF of 51 to placate mobile companies?
post #7198 of 7384
Yes. It's a petition to move KFXL from 51 to 15.

- Trip
post #7199 of 7384
Quote:
Originally Posted by BCF68 View Post

Isn't the FCC trying to get stations OFF of 51 to placate mobile companies?

Yes, they are, and LPTV stations on channel 51 have been jumping ship for several weeks now. They aren't entitled to any compensation for switching. As far as I know, this is the first full-power station to jump.
post #7200 of 7384
Quote:
Originally Posted by Trip in VA View Post

Yes. It's a petition to move KFXL from 51 to 15.

- Trip

doh! My bad.

Quote:
Originally Posted by dhett View Post

Yes, they are, and LPTV stations on channel 51 have been jumping ship for several weeks now. They aren't entitled to any compensation for switching. As far as I know, this is the first full-power station to jump.

I know there's a FP channel 51 in Memphis but I'm not sure if they have made a request to move yet. Really haven't kept up on it.

I wonder how long before the mobile companies say they need channel 50 vacated then 49 etc etc. Seems as if they can get the incetive auctions they'll just get the spectrum piecemeal. After all what is just ONE channel.
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