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AVS Official Topic - The FCC & Broadcast Spectrum - Page 87

post #2581 of 2851
12/27/11 at 4:45am
Quote:
Originally Posted by cgmv123 View Post

How? VHF was superior for everything you said, plus they carried more value with advertisers. I agree that after the FCC fixed the power levels, UHF could sometimes compete with VHF. Here in Madison, we were a "doughnut" and could only get one VHF license. The station that won the license, WISC, is still the top-rated station today. Granted WKOW sometimes gives them a run for their money, but Channel 3 usually comes on top. So you're saying that if given the choice, you would choose UHF over VHF with an analog station?

I'm saying that toward the end of the days of analog TV, on a purely technical basis I would choose UHF over VHF. Once UHF tuners began to match VHF in terms of quality and UHF transmitters got powerful enough to run at levels that would allow them to match VHF coverage better, UHF was superior. It used smaller antennas to produce superior reception and had a much easier time with electrical interference. I remember I had one of those handheld analog TVs with the stick antenna, and the low-VHFs would only come in within a few miles of the transmitter. Indoor UHF antennas could work out to many miles while low-VHF pretty much required an outdoor antenna for anything that wasn't mainly audio with snow for video.

It's actually pretty analogous to digital reception today, in my mind, if you had any standards at all for how clear an analog picture had to be to be "watchable." I found the various types of interference in low-VHF analog to be extremely distracting and unless I really needed something on those bands, usually found it to be "unwatchable."

- Trip
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post #2582 of 2851
12/27/11 at 10:08am
I depends upon your situation. High VHF is great here. I find it to be less affected by temperature inversions than UHF. The coverage is better. KGO on 7 is the most reliable station from Mt. Sutro (110 miles) and they only run 24 KW. They'd be close to 100% if they'd up their power to 75 KW. 4 dB would help a lot. None of the 1 MW UHF stations are nearly as good. KSBW on 8 is a 100% rock solid signal at 115 miles and KBCW on the same tower is 99.9% even with an antenna directed away from me with a calculated power of only 50-100 watts. No UHF station from the same location is anywhere near this good. KNSO 11 is the only Fresno station I ever see here unless conditions are exceptional then a couple UHF stations can be seen.... a few times a year.

I find UHF to be great out to 60 miles, but beyond that LOS or near LOS is more important than on high VHF.

Chuck
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post #2583 of 2851
12/27/11 at 12:11pm
I agree that UHF vs. Hi-VHF depends on the situation. UHF attenuates much faster so much higher Tx power is required to reach the same service attained by Hi-V. Also the building entry loss and its std deviation are lower for Hi-V (see ITU-R P.1812). Hi-V is also better under dynamic multipath (incl. mobile) because the lower % of Doppler shift. Hi-V's worst handicap is that small antennas do not have enough area and thus have very low radiation resistance so the absorbed power is small. Had the FCC given the Hi-V reasonable power based on realistic planning factors the VHF/UHF debate would be different. BTW, note that I did not include Lo-V which should never have been included.
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post #2584 of 2851
12/27/11 at 3:06pm
Quote:
Originally Posted by DTVintermods View Post

.......Had the FCC given the Hi-V reasonable power based on realistic planning factors the VHF/UHF debate would be different.

The FCC approved a request from WLJC-DT-7, Beattyville, KY to increase its ERP from 70 kW to 185 kW earlier this month. I live 208 miles NW of their tower site and I decode this station quite often at 70 kW whenever tropo enhancement hits the area. It will be interesting to see how the reception is after it increases to 185 kW. Plus, it will be interesting to see if local reception is easier/stronger with the hefty power increase.

https://licensing.fcc.gov/cdbs/CDBS_...um=1&exhcnum=1

http://transition.fcc.gov/fcc-bin/tv...=0&facid=27696
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post #2585 of 2851
12/27/11 at 3:21pm
Thread Starter 
Quote:
Originally Posted by coyoteaz View Post

Going from 400 to 1000kW is only like 4dB, which isn't a whole lot in the grand scheme of things.

In my area that can make a huge difference. Besides my point still stands what is the point of increasing power when stations aren't using max power NOW? As I said they can increase hi-VHF to 250 kW if they want but if stations aren't maxing out CURRENT power levels what makes you think that increasing power levels will magically make them do that?
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post #2586 of 2851
12/27/11 at 4:13pm
Quote:
Originally Posted by BCF68 View Post

In my area that can make a huge difference. Besides my point still stands what is the point of increasing power when stations aren't using max power NOW? As I said they can increase hi-VHF to 250 kW if they want but if stations aren't maxing out CURRENT power levels what makes you think that increasing power levels will magically make them do that?

I don't, I was just explaining why many of them haven't gone for increases under current rules. If you've got a transmitter that maxes out at 5kW and an antenna with 7dB of gain, then going above 20kW ERP is going to require either a higher gain antenna or another transmitter. Neither of those is a cheap proposition, and if you can't reach enough additional viewers to justify higher ad rates to cover those costs, it probably isn't going to happen. And that's not even counting interference concerns in some of the denser areas like the eastern seaboard and great lakes regions.
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post #2587 of 2851
12/27/11 at 8:49pm
Thread Starter 
Quote:
Originally Posted by coyoteaz View Post

I don't, I was just explaining why many of them haven't gone for increases under current rules. If you've got a transmitter that maxes out at 5kW and an antenna with 7dB of gain, then going above 20kW ERP is going to require either a higher gain antenna or another transmitter. Neither of those is a cheap proposition, and if you can't reach enough additional viewers to justify higher ad rates to cover those costs, it probably isn't going to happen. And that's not even counting interference concerns in some of the denser areas like the eastern seaboard and great lakes regions.

Which kind of disproves the theory of some that say that raising the power levels of hi-VHF will solves reception issues thus making hi-VHF a viable option for DTV.
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post #2588 of 2851
12/28/11 at 7:35am
Not at all. His point is stricly an economic one. The problem was starting with such low levels after building at least one new facility, if not two during the transition. Upping the power in his example is not much different from building yet another transmission plant.

I'd wager that most, if not all of the Hi-V power incerases, like the two in DC, took advantage of transmitter and antenna headroom to just turn the knob to 11 to get higher power.
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post #2589 of 2851
12/28/11 at 9:50am
San Francisco has two high VHF stations and I don't understand what their thinking is.

KGO 7 has 72 KW licensed to an auxiliary antenna low on Sutro tower. Why don't they apply to put that transmitter on the top mounted antenna? For all I know it's the same transmitter.

KNTV 12 has 103 KW but the main lobe is pointed to the Pacific Ocean with a null to the northeast. This made sense before the transition when they had to protect KHSL analog on 12 but that's history. Turning their antenna around would mean 7 dB more power in my direction. Maybe they're just lazy.

Chuck
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post #2590 of 2851
12/28/11 at 1:14pm
Money.
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post #2591 of 2851
12/28/11 at 3:33pm
Quote:
Originally Posted by Calaveras View Post

KGO 7 has 72 KW licensed to an auxiliary antenna low on Sutro tower. Why don't they apply to put that transmitter on the top mounted antenna? For all I know it's the same transmitter.

The TPO is the same on both antennas, about 8.9 kW. The difference is in the amount of line loss (extra height) and the one lower down is directional and thus has more gain.

Looking at KGO's engineering study, it looks like the 23.8 kW puts them right at the 0.5% interference limit with regard to KSBW, presumably why no further power increase has been requested.

- Trip
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post #2592 of 2851
1/1/12 at 1:03pm
Quote:
Originally Posted by Calaveras View Post

KNTV 12 has 103 KW but the main lobe is pointed to the Pacific Ocean with a null to the northeast. This made sense before the transition when they had to protect KHSL analog on 12 but that's history. Turning their antenna around would mean 7 dB more power in my direction. Maybe they're just lazy.

This is puzzling one. I'd think a market like SF would be worth the labor cost to rotate the antenna, especially for upper VHF, where indoor antennas are a concern.
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post #2593 of 2851
1/1/12 at 1:35pm
Quote:
Originally Posted by Falcon_77 View Post

This is puzzling one. I'd think a market like SF would be worth the labor cost to rotate the antenna, especially for upper VHF, where indoor antennas are a concern.

The FCC site shows there is still a slew of both analog and digital LPTV and LD's on channels 11, 12 and 13 in California, so they probably have to keep protecting those. It would take a bit more than just some labor to "turn" their transmitting antenna .
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post #2594 of 2851
1/1/12 at 2:28pm
LPs get no protection from full-powers.

- Trip
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post #2595 of 2851
1/1/12 at 3:19pm
Im a ham, and my in car radio could pick up the sound carriers for the old analog stations. I'd sometimes listen to a program while driving. What I found driving around NYC and the Albany markets was that VHF low didn't go as far. The VHF high channels were better but more line of sight. Probably the best channels for getting over hills and still sending a readable signal were vhf four and five.

UHF is a line of sight band. You will not get the significant diffraction over a hill or two that you got with VHF high or upper VHF low. I had one route it took where I would get channel 7 and 5. When I got to the top of the hill, two would come in for a bit, but I'd keep four, five and seven the longest. If I could pick, I'd want VHF low four for my broadcast. VHF two was worst choice by far.

Luckily, I have a line of sight to NYC broadcasters, but UHF is lots less forgiving. I'm not at all surprised that lots of fringe folks lost service

I am peeved that the FCC allowed in the NYC dma a low power religious broadcaster on VHF 2. My ota setup will lock onto this as 2.1 and 2.2 causing confusion with wcbs the real channel two. My ota antenna is too good
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post #2596 of 2851
1/1/12 at 8:00pm
Quote:
Originally Posted by Falcon_77 View Post

This is puzzling one. I'd think a market like SF would be worth the labor cost to rotate the antenna, especially for upper VHF, where indoor antennas are a concern.

If you take a look at KNTV's antenna pattern, you'll see that it's perfectly oriented for their intended market.

http://www.fcc.gov/fcc-bin/polarplot...82&p360=0.563&

Ron
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post #2597 of 2851
1/1/12 at 8:35pm
As long as the intended market lives in the Pacific and not in places like Oakland.

- Trip
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post #2598 of 2851
1/2/12 at 4:58am
Quote:
Originally Posted by Trip in VA View Post

LPs get no protection from full-powers.
- Trip

Yeah, I know that, but in the court of public opinion, they'd still look like the bad guy if they forced some low powers off the channel, especially if someone "spins" it to say they were trying to "eliminate competition".
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post #2599 of 2851
1/2/12 at 5:00am
Quote:
Originally Posted by Trip in VA View Post

As long as the intended market lives in the Pacific and not in places like Oakland.

- Trip

Darn...you got me thinking....
How is reception on a sailboat? I wonder how many people use their TV's out there along the coastal waters?
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post #2600 of 2851
1/2/12 at 7:59am
Quote:
Originally Posted by Falcon_77 View Post

This is puzzling one. I'd think a market like SF would be worth the labor cost to rotate the antenna, especially for upper VHF, where indoor antennas are a concern.

There would be no benefit to doing so, due to the topography of the Bay Area. Regardless of the antenna pattern or broadcast band, the effective coverage of all of the main stations is about the same: all of the communities directly bordering on the bay. That covers the majority of the population in the market. Unless you're willing to put a fill-in translator on Mt. Diablo, you're not going to get good OTA coverage in eastern Alameda and Contra Costa counties.

KTVU RF 44: http://www.rabbitears.info/contour.p...=1423741&map=Y
KRON RF 38: http://www.rabbitears.info/contour.p...=1341221&map=Y
KPIX RF 29: http://www.rabbitears.info/contour.p...=1340821&map=Y
KGO RF 7: http://www.rabbitears.info/contour.p...=1329792&map=Y
KQED RF 30: http://www.rabbitears.info/contour.p...=1356714&map=Y
KNTV RF 12: http://www.rabbitears.info/contour.p...=1087047&map=Y

The only station whose coverage seems to suffer a bit is KGO, and as Trip pointed out, they're limited by adjacent channel KSBW, so they use a fill-in translator on ch 35 to cover the South Bay.
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post #2601 of 2851
1/3/12 at 6:03pm
Quote:
Originally Posted by dhett View Post

There would be no benefit to doing so, due to the topography of the Bay Area.

No benefit? I wouldn't say that. Yes, I see that the East Bay is all in green, but remember that not everyone has a Yagi on their roof. The green is a general guide and I know of plenty of situations where it is not good enough for an indoor antenna (e.g., stucco, buildings in the way and low-E glass). I also know that San Jose is the COL, but most stations care about covering more than 1 city and flipping the antenna pattern won't greatly affect San Jose.

In any event, as already noted, the orientation is a hold-over from the analog days. See the following from their CP application:

https://licensing.fcc.gov/cdbs/CDBS_...um=1&exhcnum=1

If nothing else, the current pattern is inefficient.
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post #2602 of 2851
1/3/12 at 8:29pm
Quote:
Originally Posted by Falcon_77 View Post

No benefit? I wouldn't say that.

It would be splitting hairs. Oakland is only 12 miles from the transmitter. KNTV is about 60 dB above the noise at that location. If they rotate their antenna, they'll be 63.5 db above the noise.

Ron
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post #2603 of 2851
1/4/12 at 4:56am
Trouble is...especially with VHF channels...there has to be a standard for all the parts of the signal path. The power, the transmit antenna, the receive antenna, the receiver sensitivity, etc....all of those enter in to the allocation process calculations.

If we have to provide service that works for all the indoor antennas, them we have to allocate channels as if everybody just has indoor antennas. So, we'd have to increase power drastically, and assume that everybody's signals are blocked by stucco anyway. Then, everybody with outdoor antennas has problems with interference from high-powered stations on that same channel, coming from the next city, interference that "should be blocked by basement walls", so to speak.

That's why the allocations were based on a "standard" receive setup, which was a reasonable outdoor antenna (sort of a compromise between indoor and outdoor antennas).
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post #2604 of 2851
1/4/12 at 8:01am
Quote:
Originally Posted by kenglish View Post

That's why the allocations were based on a "standard" receive setup, which was a reasonable outdoor antenna (sort of a compromise between indoor and outdoor antennas).

There's also the matter of how data to support propagation modeling was collected - this leads to planning factors like assuming a 30 foot receive antenna height.
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post #2605 of 2851
1/4/12 at 8:43am
Quote:
Originally Posted by Dave Loudin View Post

There's also the matter of how data to support propagation modeling was collected - this leads to planning factors like assuming a 30 foot receive antenna height.

30 feet above ground level is not a bad "standard" for making computations. A decent antenna on a two-story house or a small office building or MDU is not far-fetched. It also is a good rule-of-thumb height to get above the clutter of trees, people, and cars. Trying to make computations at anything lower would involve variables like the above, plus small animals .

They're not "assuming" that everybody has a thirty foot tower, they are using a mathematical "assumption", a fixed number, as part of the total
equation. The satellite re-sellers like to toss out that "30-foot antenna" thing, to make people figure they need a monster antenna in every case, to get OTA.

Also, 30-feet is the recognized standard for the measurements that have always been collected on RF in general. Tests are done with a 30-foot mast, and a signal-strength meter, driving over specific short paths and normalizing the results. Those then are matrixed in to the larger area maps.
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post #2606 of 2851
1/4/12 at 8:56am
On the subject of Government/Municipalities building broadband systems with tax money:

http://www.ksl.com/?nid=960&sid=1872...in-iprovo-debt
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post #2607 of 2851
1/4/12 at 8:55pm
In an ideal world, a 30 foot antenna would be needed only in far outlying parts of a market, or for DXing. I believe that everyone living in the main city of a market should be able to receive all local stations including low power stations with rabbit ears. Here in Bakersfield in my garage and backyard, or in the house or trailer with the A/B switch switched to antenna, I can easily get full power RF 25, 33, and 45. Full power RF 10 and low power RF 18, 34, 39, and 46 require minimal adjusting of the rabbit ears to lock on. Low power RF 19, 29, and 31 sometimes require extensive adjusting of the rabbit ears to lock on and still may pixellate. The low power analogs range from light snow to unwatchable no matter what I do with the antenna.
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post #2608 of 2851
1/12/12 at 11:08am
CES Overwhelms With Tech and Policy

http://www.tvtechnology.com/article/...-policy/211282

Quote:


Spectrum overhaul loomed over many CES conference sessions, especially the one-on-one chat between Genachowski and CEA chief Gary Shapiro (pictured above), an ardent advocate of shifting airwaves assignments to non-broadcast uses. To defend has advocacy of incentive spectrum auctions, Genachowski pointed out that New York City has 28 broadcast channels.

“No one thinks 28 is the right number for New York,” he said. “What is the right number? The wonderful part of the incentive auctions is that it will let the market decide.”

Genachowski also touched on unlicensed spectrum, stressing that “everything is connected wirelessly” and hence, “We should work on unleashing more of it,” referring to spectrum. The chairman also repeated his belief that the Communications Act, which governs the regulation of TV and telecom services, should be updated, vowing to help Congress revise the Act, but offering no expectation of imminent action. He concluded by saying that he is proud that his legacy at the FCC will be “that we focused on broadband.”
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post #2609 of 2851
1/18/12 at 1:13pm
FCC Seeks Unbounded Spectrum Auction Authority

http://www.forbes.com/sites/scottcle...ion-authority/

Quote:


At CES, the FCC signaled that it opposed any effort by Congress to give the FCC policy direction or to establish any checks and balances on the FCC in authorizing incentive auctions of prime TV broadcast spectrum. The FCC's lack of regulatory humility here is stunning.

Remarkably an unelected FCC, whose entire authority and legitimacy comes from Congress, is trying to tell Congress to abandon its Constitutional role and delegate unbounded revenue-raising authority to the FCC.

More remarkably, the FCC is specifically flouting Article I Section 7 of the Constitution All bills for raising revenue shall originate in the House of Representatives in expecting the House to originate a revenue-raising bill that would grant the FCC carte blanche to raise, or not raise, revenues for the U.S. Treasury at the FCC's sole discretion.

Even more remarkably, the FCC is requesting unbounded authority when it knows it fundamentally disagrees with Congress' primary purpose for auctioning the spectrum, i.e. to use market forces to maximize revenues for the taxpayer and allocate spectrum to those who value it the most.

Yet even more remarkably, the FCC specifically wants unilateral unchecked power to first give away many billions of dollars of taxpayers' money in free unlicensed spectrum, and second to pick-and-choose who can and cannot be eligible to bid in ways that would sub-optimize the value and utility of the spectrum and also shortchange the U.S. taxpayer by many more billions of dollars in foregone auction revenues...
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post #2610 of 2851
1/18/12 at 1:20pm
"Spectrum overhaul loomed over many CES conference sessions, especially the one-on-one chat between Genachowski and CEA chief Gary Shapiro (pictured above), an ardent advocate of shifting airwaves assignments to non-broadcast uses. To defend has advocacy of incentive spectrum auctions, Genachowski pointed out that New York City has 28 broadcast channels.

No one thinks 28 is the right number for New York, he said. What is the right number? The wonderful part of the incentive auctions is that it will let the market decide.

"Let the Market Decide".....how many under-engineered-but-vigorously-marketed products have flown under THAT banner?
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