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The vast majority of local signals are sent by cable (usually fiber) to a central station where they are then sent by satellite to D*'s main facility and being recoded (from MPEG2 to MPEG4) go from there back to satellite to your receiver. I understand that in some cases D* uses an antenna to receive the signal, but I believe that fiber is the norm.


SMK
 

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Quote:
Originally Posted by RoyGBiv /forum/post/16987635


The vast majority of local signals are sent by cable (usually fiber) to a central station where they are then sent by satellite to D*'s main facility and being recoded (from MPEG2 to MPEG4) go from there back to satellite to your receiver. I understand that in some cases D* uses an antenna to receive the signal, but I believe that fiber is the norm.


SMK

Yes, The part with an OTC receiver, I have an HR 20-200 it has #2 ATSC tuners. You also get the satellite signal. The second part, fiber-optics to a central station , I didn't know, Thanks.


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As I understand it, it is the responsibility of the broadcast station to get its signal to the DirecTV Point of Presence. Initially, with analog, most of them were simply broadcasting it, but I woudn't be surprised if most of the TV stations are now paying the cost of fiber carriage because a single bad frame of digital distupts and freezes a picture for a second, whereas a single bad frame of analog usually goes unnoticed.


Back when DBS bandswidth was more scarce than it is today, I remember both DirecTV and DISH being accused of deliberately locating some of their Point of Presence reception sites inconveniently for reception of signals from weak, less desirable independent television stations.
 

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My understanding is that antenna is the primary choice, with fiber only being used in the case of certain stations where an antenna is unusable. In fact, I've heard from some stations that offered a fiber feed to D* that D* rejected the offer in favor of continuing to use the antenna.


D* has a list of all their receive sites on their website . I know that a lot of them are shared with Dish to cut down on costs.
 

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Quote:
Originally Posted by AntAltMike /forum/post/16988082


As I understand it, it is the responsibility of the broadcast station to get its signal to the DirecTV Point of Presence.

Not what I've been told.
 

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Quote:
Originally Posted by coyoteaz /forum/post/16988493


My understanding is that antenna is the primary choice....

Agree.
 

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Quote:
Originally Posted by Ken H /forum/post/16992026


Not what I've been told.

The rules regarding DBS carriage of locals were intended to replicate those regarding cable TV, as closely as possible. With cable TV, it is the station's responsibility to get the signal to the cable company to qualify for mandatory carriage. There are threads here in which the minimum signal standards were listed. I think there was one level for VHF low, one for VHF high and one for UHF, and I think the range of those minimum signal level at the cable company headend ranged from zero to -4dBmV for analog, and I think they were all -4dBmV for digital, but I'm not sure how I'd go about searching for that thread.


The Washington, DC DMA includes a distant station from Hagerstown that DBS satellite would never voluntarily carry, and which I seriously doubt could be received at the point of presence, but it is on DirecTV and DISH, so I assume they find it worth their while to pay for fiber carriage to assure carriage in a much, much larger market than they could possibly reach with broadcast signals.
 

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So if stations are responsible for getting their signals to cable/DBS pickup points, how many of them are delivering bit rates of network/local programming that don't include bit rate reductions caused by multicasting of subchannels? If stations aren't using separate encoders for this, different than their OTA encoders, it seems much (or all) of the blocking artifacts and PQ reductions (resolution-wise) seen from DBS or cable would be the stations fault. Additional on-the-fly rate shaping with requantization at cable/DBS head ends might be a factor, too. -- John
 

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It's more like a combination of both the station and the DBS provider. DBS can only be "as good as" the broadcast that they are receiving.


Now, cable in some cases DOES have fiber from the station to the cable company headend - I know that is happening here in Raleigh. WRAL has/had some fiber, and so does WUNC.
 

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Quote:
Originally Posted by AntAltMike /forum/post/16992178


The rules regarding DBS carriage of locals were intended to replicate those regarding cable TV, as closely as possible. als.

Technical reps from both D* & E* have told me it's up to them exclusively to acquire local HD for their systems.
 

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Here in the Sacramento market both D* and E* get the local stations OTA. D* was getting the local analog VHF stations via fiber that D* paid for because they had a local interference problem at their receive point. Both cable carriers and AT&T get both digital channel and analog feeds via fiber that they (the carrier) installed from most if not all stations.
 

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Most off-air stations are received by the DirecTv Local Receive Facility off-air, using an antenna; fiber is less common. So the signal they receive will already show the effects of running multiple subchannels if that is what the station is doing. DirecTV then re-encodes the MPEG-2 signal from the station to MPEG-4 - since these coding schemes are both "lossy", there is some loss of information in the re-encoding, which means that the DirecTV signal can never be better than the off-air signal and typically will be slightly worse. With good setup on the encoders, it's difficult to see the difference - here in DFW for most of the stations for much of the time the visible picture quality on a 52in TV is the same.

The other issue with the re-encoding is the effect of glitches in the signal. Tyoically a small glitch in the MPEG-2 signal will result in a bigger glitch in the MPEG-4 signal because the encoder loses sync for a longer time. Same with issues with the Dolby Digital bitstream - see all the posts in various forums on the "brrrp" problem.
 

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Quote:
Originally Posted by John Mason /forum/post/16992357


So if stations are responsible for getting their signals to cable/DBS pickup points, how many of them are delivering bit rates of network/local programming that don't include bit rate reductions caused by multicasting of subchannels? If stations aren't using separate encoders for this, different than their OTA encoders, it seems much (or all) of the blocking artifacts and PQ reductions (resolution-wise) seen from DBS or cable would be the stations fault. Additional on-the-fly rate shaping with requantization at cable/DBS head ends might be a factor, too. -- John

About 2 yrs ago & spoke to the VP of engineering for our PBS station. He said Comcast did not add any compression to the station's signal. That whatever the station sends out is what Comcast sends out. The discussion was really about another topic so I never asked how the signal got to Comcast. But is was interesting to hear that Comcast did not add any compression.
 

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Quote:
Originally Posted by Mike99 /forum/post/17005823


About 2 yrs ago & spoke to the VP of engineering for our PBS station. He said Comcast did not add any compression to the station's signal. That whatever the station sends out is what Comcast sends out. The discussion was really about another topic so I never asked how the signal got to Comcast. But is was interesting to hear that Comcast did not add any compression.

That was true then but it certainly isn't true now. Comcast nationally used to put two HD channels into each QAM channel but now allocates three channels per QAM channel. Here's an interesting thread from last year http://www.avsforum.com/avs-vb/showthread.php?t=1008271
 

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Quote:
Originally Posted by texasbrit /forum/post/17009937


That was true then but it certainly isn't true now.

Sure it is, for local HD channels, which are still 2 per QAM, meaning no additional compression.

Quote:
Comcast nationally used to put two HD channels into each QAM channel but now allocates three channels per QAM channel.

Correct, national HD channels are 3 per QAM.
 

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Before the

Federal Communications Commission

Washington, D.C. 20554



In the Matter of:

-Implementation of the Satellite Home Viewer Improvement Act of 1999

-Broadcast Signal Carriage Issues CS Docket No. 00-96

-Retransmission Consent Issues CS Docket No. 99-363

REPORT AND ORDER


Adopted: November 29, 2000 Released: November 30, 2000


By the Commission:

TABLE OF CONTENTS


Paragraph

I. INTRODUCTION 1



SATELLITE BROADCAST SIGNAL CARRIAGE 10


D. Receive Facilities 43

1. Local Receive Facilities 45

2. Alternative Receive Facilities 49


J. Digital Television 120



INTRODUCTION


Section 338 of the Communications Act of 1934 (“Act”), adopted as part of the Satellite Home Viewer Improvement Act of 1999 (“SHVIA”) requires satellite carriers, by January 1, 2002, “to carry upon request all local television broadcast stations’ signals in local markets in which the satellite carriers carry at least one television broadcast station signal,” subject to the other carriage provisions contained in the Act...


D. Receive Facilities


Section 338(b)(1) states that, “A television broadcast station asserting its right to carriage under subsection (a) shall be required to bear the costs associated with delivering a good quality signal to the designated local receive facility of the satellite carrier or to another facility that is acceptable to at least one-half the stations asserting the right to carriage in the local market.”...


1. Local Receive Facilities


In the definition of “local receive facility” in Section 338(h)(2), the satellite carrier is the entity authorized to designate the placement of a local receive facility. If the satellite carrier designates a local receive facility, the television broadcast stations are required by the statute to bear the costs of delivering a good quality signal to “the designated local receive facility of the satellite carrier.” We find that the statute expressly provides that the satellite carrier has the right to determine the location of the local receive facility. We disagree with the proposals offered by AAPTS and Network Affiliates to require a satellite carrier to locate a receive facility either within the Grade B contour or not more than 50 miles from the community of license of each of the local stations in a market. ..


2. Alternative Receive Facility


...a satellite carrier’s local receive facility is the equivalent of a cable system’s headend. We do not believe that the statute requires, nor that any party contemplates, that television stations can unilaterally select a site and force a satellite carrier to construct a facility or move its receive facility there.


As noted above, the statute assigns costs to the broadcaster when providing the satellite carrier with a good quality signal to either a local or alternative facility. We agree, therefore, with BellSouth that a satellite carrier is not obligated to carry a television broadcast station that refuses to pay for the costs of providing a good quality signal. For similar reasons, we disagree with Network Affiliates’ proposal that if the carrier uses an alternative facility, which at least half of the local stations find acceptable, then the satellite carrier should pay the incremental costs of delivering each broadcaster’s signal if the alternative facility is more than 50 miles from the reference point of the station’s community of license.


3. Notification


We decline to establish a special complaint standard or process for disputes concerning alternative receive facility disputes...


...We... decline to adopt a good faith test to be used in the context of receive point negotiations.


5. Good Quality Signal


Standard: ...Under the current cable carriage regime, television broadcast stations must deliver either a signal level of -45dBm for UHF signals or -49dBm for VHF signals at the input terminals of the signal processing equipment, to be considered eligible for carriage....


DirecTV states that the Commission should define “good quality signal” as one that will facilitate efficient MPEG compression of all channels. ...We decline to adopt DirecTV’s good quality signal proposals for several reasons. First, we believe that the TV1 standard is too rigid a construct. .... Moreover, ...satellite carriers, such as Echostar, have been retransmitting local television signals that they have received over-the-air without much concern about signal quality (AntAltMike note: HaHaHaHA!).


We decide to apply the current good quality signal standards applicable in the cable context to satellite carriers...A television station may use microwave transmissions, fiber optic cable, or telephone lines as long as they pay for the costs of such delivery mechanisms. Such alternative delivery methods are sanctioned under the cable carriage rules and should be applicable in the satellite carriage context.


Carriage of Television Stations With Disputed Signal Quality. In the Notice, we recognized that a broadcaster not providing a good quality signal to a cable system headend is not qualified for carriage....



Good Signal Quality Measurement and Testing. With respect to the manner of testing for a good quality signal, we note that the Commission has adopted a method for measuring signal strength in the cable carriage context. Generally, if a test measuring signal strength results in an initial reading of less than ‑51 dBm for a UHF station, at least four readings must be taken over a two‑hour period. If the initial readings are between ‑51 dBm and ‑45 dBm, inclusive, readings must be taken over a 24‑hour period with measurements not more than four hours apart to establish reliable test results. For a VHF station, if the initial readings are less than ‑55 dBm, at least four readings must be taken over a two‑hour period. Where the initial readings are between ‑55 dBm and ‑49 dBm, inclusive, readings should be taken over a 24‑hour period, with measurements no more than four hours apart to establish reliable test results...


We believe that the signal testing practices in the cable carriage context should be generally applied in the satellite carriage context. ....


J. Digital Television


The Commission has adopted rules establishing a transitional process for the conversion from an analog to a digital form of broadcast transmission. The rules allow each existing analog television licensee or each eligible permittee to construct and operate digital facilities using 6 MHz of spectrum, in addition to the 6 MHz of spectrum used to continue analog broadcasting until the end of the transition. The broadcast station will transmit a signal consistent with the standards adopted in Advanced Television Systems and Their Impact Upon the Existing Television Broadcast Service, Fourth Report and Order, giving it the flexibility to broadcast in a high definition mode, in a multiple program standard definition mode, in a datacasting mode, or a mixture of all three, provided that the licensee provides at least one over-the-air video program stream to consumers. ...


ORDERING CLAUSES


...IT IS ORDERED that..., the Commission’s rules ARE HEREBY AMENDED


Federal Communications Commission



Magalie Roman Salas

Secretary
 

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Quote:
Originally Posted by AntAltMike /forum/post/17010327


Before the

Federal Communications Commission

Washington, D.C. 20554



In the Matter of:

-Implementation of the Satellite Home Viewer Improvement Act of 1999

-Broadcast Signal Carriage Issues CS Docket No. 00-96

-Retransmission Consent Issues CS Docket No. 99-363

As we all know, the FCC is notorious for not enforcing many of the rules and regulations they put into the record. The sources I referenced were in the position to know what they were saying, one of them was a VP of engineering for a US DBS provider.
 

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Quote:
Originally Posted by Ken H /forum/post/17010083


Sure it is, for local HD channels, which are still 2 per QAM, meaning no additional compression.


Correct, national HD channels are 3 per QAM.

Most national channels are 3:1, but not all. There are some channels that are 2:1 such as ESPN, ESPN2, and a few others. Typically this is the case because of the need to do regional blackouts for sports networks or they do not yet have carry the network as part of any of the 3:1 Muxs coming out of the Comcast Media Center.
 
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