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Is clustering of frequencies/affiliates gone with HDTV?

The subject of the thread may be a bit confusing, so I'll explain:

In most markets that I have been to, there is a clustering of tv statoins on one end of the analogue tv band or the other. For example, In Boston Network stations appear to be on clustered on the low end, 2, 4, 5, and 7. However, in Providence Rhode Island, everything is on 6, 10, and 12, with the newer stations over on UHF.

Which leads me to the question, is there any clustering with the new DT frequencies? I notice alot of markets where some stations are 21, another on 54, etc... Which has me concerned. Won't that really diminish the viewership? It sounds like many viewers are going to have to really wander around to find the local stations.

Or am I not getting the whole picture on this? Please tell me (in a nice and kindly way), if there will be clustering in HDTV, if the lower single digits will remain, etc. What am I missing about this?

Thanks.
 
> Or am I not getting the whole picture on this? Please tell
> me (in a nice and kindly way), if there will be clustering
> in HDTV, if the lower single digits will remain, etc. What
> am I missing about this?

What you're missing - and it's been pointed out often enough here, sometimes in response to your own posts, that I'm beginning to wonder if I'm not stepping into trollbait here - is that from the perspective of the viewer, nobody's changing channels, thanks to the magic of remapping.

When I turn on my DTV set-top box to watch my Rochester locals, I'm not tuning in "45," "58," "59," "16" and "28" - I'm watching 8.1, 10.1, 13.1, 21.1 and 31.1, just like I did with analog, and just as Boston viewers can tune to 2.1, 4.1, 5.1, 7.1, and so on. That the box is internally tuning to channels 19, 30, 20, 42, etc. is of no relevance to the viewer, any more than you're already aware that you're tuning in 66-72 MHz when the box says "4".

That make sense?<P ID="signature">______________
Tower Site Calendar 2006 JUST RELEASED! - <a target="_blank" href=http://www.fybush.com/nerw.html#calendar>www.fybush.com</a></P>
 
> Or am I not getting the whole picture on this? Please tell
> me (in a nice and kindly way), if there will be clustering
> in HDTV, if the lower single digits will remain, etc. What
> am I missing about this?
----------

As it stands now, Detroit has the following DT frequencies:

06 CIII-DT-22 (Global) - proposed
14 WKBD-DT (UPN)
21 WDWB-DT (WB)
35 CBET-DT (CBC) - proposed
39 WADL-DT
41 WXYZ-DT (ABC)
43 WTVS-DT (PBS)
44 WWJ-DT (CBS)
45 WDIV-DT (NBC)
58 WJBK-DT (FOX)
65 CHWI-DT-60 - proposed
68 CICO-DT-32 (TVO) - proposed
69 CBEFT-DT (SRC) - proposed

So, four of the Detroit stations are clustered in the low-to-mid 40s, and three of the five Windsor-area stations just across the river are in the mid-to-high 60s.

Very few DTV stations are going to be on VHF (particularly channels 2-6) - as you can see only one of the 13 full-power stations in the Detroit/Windsor area are planned to be on VHF. I know a few stations are planning to return to their present NTSC allocation after the full move to digital. WWNY Carthage/Watertown is supposed to revert back to channel 7, and I believe WHEC Rochester is supposed to revert back to channel 10.<P ID="signature">______________
From WNBC-TV New York this is Liiiiive at Fiiiiive!</P>
 
> > Or am I not getting the whole picture on this? Please tell
>
> > me (in a nice and kindly way), if there will be clustering
>
> > in HDTV, if the lower single digits will remain, etc.
> What
> > am I missing about this?
>
> What you're missing - and it's been pointed out often enough
> here, sometimes in response to your own posts, that I'm
> beginning to wonder if I'm not stepping into trollbait here
> - is that from the perspective of the viewer, nobody's
> changing channels, thanks to the magic of remapping.
>
> When I turn on my DTV set-top box to watch my Rochester
> locals, I'm not tuning in "45," "58," "59," "16" and "28" -
> I'm watching 8.1, 10.1, 13.1, 21.1 and 31.1, just like I did
> with analog, and just as Boston viewers can tune to 2.1,
> 4.1, 5.1, 7.1, and so on. That the box is internally tuning
> to channels 19, 30, 20, 42, etc. is of no relevance to the
> viewer, any more than you're already aware that you're
> tuning in 66-72 MHz when the box says "4".
>
> That make sense?

That is correct, however mapping has have issues, it doesn't always work, so you will need to know the correct channel number. Hopefully this will be a non issue with better converters

However another bump to mapping is several manufacturers have said if they can make digital to analog converters without ANY extra stuff, such as PSIP mapping they can do it for under $10.00. This means the issue of mapping isn't a done deal yet.

So it's possible, but not likely, yet possible all DTV tuners will have mapping but not all converters (digital to analog) will.
>
<P ID="signature">______________
Once I figured out the meaning of life....Then I forgot to write it down.</P>
 
> So it's possible, but not likely, yet possible all DTV
> tuners will have mapping but not all converters (digital to
> analog) will.

Possible, yes, but highly unlikely. Any DTV tuner or converter that the FCC will approve for use in the U.S. will have to comply with the ATSC's standards for digital television, and the use of PSIP and mapping has been a mandatory part of those standards for several years now. It would seem to me that those PSIP/mapping functions would be an integral part of any DTV tuner chip that would be used in such a box, anyway.

As the plummeting cost of DVD players proves, what reduces prices in today's electronics world is not reducing complexity, it's sheer volume. Even the most bargain-basement $34 DVD player today can play DVDs, CDs, MP3s, etc., because that capability is part of the standard chipset that's now manufactured in such enormous volume. When (and at this point it's not "if" anymore) ATSC reception capability becomes mandatory in even the cheapest TV set, that volume will be there for DTV tuner chipsets as well.

As for mapping sometimes not working, that's an issue with broadcasters not properly configuring their PSIPs, and it's going away pretty quickly.<P ID="signature">______________
Tower Site Calendar 2006 JUST RELEASED! - <a target="_blank" href=http://www.fybush.com/nerw.html#calendar>www.fybush.com</a></P>
 
Yeah, now I kinda get it.

I guess then, what I don't get is how the "re-mapping" will work?
How will the machine know to do this?
And why don't the station need to id their "re-mapped" frequency?
Or do they?

I'll be there's a link that explains this, huh?



> What you're missing - and it's been pointed out often enough
> here, sometimes in response to your own posts, that I'm
> beginning to wonder if I'm not stepping into trollbait here
> - is that from the perspective of the viewer, nobody's
> changing channels, thanks to the magic of remapping.
>
> When I turn on my DTV set-top box to watch my Rochester
> locals, I'm not tuning in "45," "58," "59," "16" and "28" -
> I'm watching 8.1, 10.1, 13.1, 21.1 and 31.1, just like I did
> with analog, and just as Boston viewers can tune to 2.1,
> 4.1, 5.1, 7.1, and so on. That the box is internally tuning
> to channels 19, 30, 20, 42, etc. is of no relevance to the
> viewer, any more than you're already aware that you're
> tuning in 66-72 MHz when the box says "4".
>
> That make sense?
>
 
> Yeah, now I kinda get it.
>
> I guess then, what I don't get is how the "re-mapping" will
> work?
> How will the machine know to do this?
> And why don't the station need to id their "re-mapped"
> frequency?
> Or do they?
>
> I'll be there's a link that explains this, huh?

Each DTV station transmits a data stream called PSIP, which tells the receiver how to handle the signal coming from the station - how many subchannels it's running, what the station's ID is, and - most critically in this case - what the station's virtual channel number is.

When you first set up your DTV receiver, you do a scan of the entire frequency spectrum. If everything's working as it should, the receiver will find and identify each of your local channels and remap them internally. If you're in Boston and you punch in "4" on your DTV tuner, once it's done the bandscan and remapped, the tuner will know (from the PSIP data it's received) that it should tune internally to channel 30 for WBZ-DT. You never need to know that, though - you just hit "4" and up comes WBZ, just as it always has.

The whole thing's designed to be as transparent as possible to the casual viewer.<P ID="signature">______________
Tower Site Calendar 2006 JUST RELEASED! - <a target="_blank" href=http://www.fybush.com/nerw.html#calendar>www.fybush.com</a></P>
 
Then there's DXing!

Those of us who do poke the channels manually, in hopes of finding DX can end up with a huge number of Channels on the same channel.
I can pick up 3 or 4 different channel 11's, and they all remap to 11. The digital numbers are all different of course. I don't think an OTA box is good enough to distinguish between two channels actually on the same digital channel.

I get Channel 31-1 which remaps to channel 8 in Lincoln Nebraska. When they go off it's not uncommon go get Channel 31-1 in Des Moines, which also happens to be 8. I dount I could ever get them both, though.



> That is correct, however mapping has have issues, it doesn't
> always work, so you will need to know the correct channel
> number. Hopefully this will be a non issue with better
> converters
>
> However another bump to mapping is several manufacturers
> have said if they can make digital to analog converters
> without ANY extra stuff, such as PSIP mapping they can do it
> for under $10.00. This means the issue of mapping isn't a
> done deal yet.
>
> So it's possible, but not likely, yet possible all DTV
> tuners will have mapping but not all converters (digital to
> analog) will.
> >
>
 
> The whole thing's designed to be as transparent as possible
> to the casual viewer.

For the most part you're correct. I can foresee one minor exception where the change won't be so transparent: Scranton/Wilkes-Barre. They've always been a UHF-only market but WBRE and WYOU are going to stay with their DTV allocations of 11 and 13, respectively. Although the market was ranked by Nielsen in 2000 as top-10 in cable penetration with 82%, anecdotal evidence suggests that a lot of people are still getting their TV off the air, especially in Wilkes-Barre, where most of the broadcast towers are located, and where the cable company has a very bad reputation. The area also has a very high percentage of poor and elderly residents.

So here's the problem: Granny has two UHF antennas attached to her chimney so she can get all of the stations. Now you're telling her that she also needs a VHF antenna to get channels 22 and 28, which aren't even VHF as far as she's concerned.

No matter what the FCC does, it ain't perfect. I wonder if it would have just been easier to have had the stations use their actual channel assignments. Yeah, there'd have been much weeping and gnashing of teeth, especially from the low-VHF and out-of-core stations, but people are resilient and seem to do OK absorbing cable channel lineup changes. There would have been some confusion at first, but people would soon adapt. Too late to change things now, but that's my 2 cents worth.
 
> So here's the problem: Granny has two UHF antennas attached
> to her chimney so she can get all of the stations. Now
> you're telling her that she also needs a VHF antenna to get
> channels 22 and 28, which aren't even VHF as far as she's
> concerned.
>
> No matter what the FCC does, it ain't perfect. I wonder if
> it would have just been easier to have had the stations use
> their actual channel assignments. Yeah, there'd have been
> much weeping and gnashing of teeth, especially from the
> low-VHF and out-of-core stations, but people are resilient
> and seem to do OK absorbing cable channel lineup changes.
> There would have been some confusion at first, but people
> would soon adapt. Too late to change things now, but that's
> my 2 cents worth.
>
Well actually they'd be better off just wiping out the assignments and starting over fresh. I'm sure the networks would like to do away with TV markets and just feed the shows to you fresh.

There was even a plan to put all the WBs on Channel 75, so that no matter where you were every WB station would map to 75 and you could find it there. (In addition to it's own mapping channel.

And there are even cases (rare as they are) like in South New Jersey or Delaware where people get TWO channel 2s. One from Baltimore and one from NYC. Both mapping to channel 2.

It'll take awhile to get it sorted out.

But the BIG question is.... Why not bring Channel ONE back??

:eek:)

<P ID="signature">______________
Once I figured out the meaning of life....Then I forgot to write it down.</P>
 
> Well actually they'd be better off just wiping out the
> assignments and starting over fresh. I'm sure the networks
> would like to do away with TV markets and just feed the
> shows to you fresh.

Now if they could only find a fresh TV show to feed us... :)
 
Could they remapped with all of
ABC stations on Channel 2,
CBS on channel 3,
NBC on Channel 4,
FOX on Channel 5,
WB on Channel 6,
UPN on CHannel 7,
PBS on Channel 8,
I on CHannel 9,
Univision on CHannel 10,
Telemundo on CHannel 11,
Telefutra on Channel 12,
TBN on Channel 13,
Daystar on Channel 14,
anything else on channel 15 and beyond?
 
> > So it's possible, but not likely, yet possible all DTV
> > tuners will have mapping but not all converters (digital
> to
> > analog) will.
>
> Possible, yes, but highly unlikely. Any DTV tuner or
> converter that the FCC will approve for use in the U.S. will
> have to comply with the ATSC's standards for digital
> television, and the use of PSIP and mapping has been a
> mandatory part of those standards for several years now. It
> would seem to me that those PSIP/mapping functions would be
> an integral part of any DTV tuner chip that would be used in
> such a box, anyway.
>
> As the plummeting cost of DVD players proves, what reduces
> prices in today's electronics world is not reducing
> complexity, it's sheer volume. Even the most
> bargain-basement $34 DVD player today can play DVDs, CDs,
> MP3s, etc., because that capability is part of the standard
> chipset that's now manufactured in such enormous volume.
> When (and at this point it's not "if" anymore) ATSC
> reception capability becomes mandatory in even the cheapest
> TV set, that volume will be there for DTV tuner chipsets as
> well.
>
> As for mapping sometimes not working, that's an issue with
> broadcasters not properly configuring their PSIPs, and it's
> going away pretty quickly.
>
I have asked this before but never received an answer:
Let's take the case of WFMY, analog 2, digital 51, in
Greensboro, NC. True, they plug the fact that their
regular schedule is on 2-1, while a 24-hour news and
weather service is on 2-2. What I want to know is,
how much difficulty would a viewer in, say, Danville, VA,
50 miles away, have pulling in WFMY-DT, even with a UHF
antenna?

I do know where the Big Four affiliates in Atlanta will be:

WSB (ABC) analog 2, digital 39
WAGA (Fox) analog 5, digital 27
WXIA (NBC) analog 11, digital 10
WGCL (CBS) analog 46, digital 19

How difficult will it be to receive these in Athens,
70 miles away?
 
> Well actually they'd be better off just wiping out the
> assignments and starting over fresh. I'm sure the networks
> would like to do away with TV markets and just feed the
> shows to you fresh.
>
> There was even a plan to put all the WBs on Channel 75, so
> that no matter where you were every WB station would map to
> 75 and you could find it there. (In addition to it's own
> mapping channel.
>
> And there are even cases (rare as they are) like in South
> New Jersey or Delaware where people get TWO channel 2s. One
> from Baltimore and one from NYC. Both mapping to channel 2.
>
> It'll take awhile to get it sorted out.
>
> But the BIG question is.... Why not bring Channel ONE back??

Actually, the system allows stations choose any number between 1 and 99 for their digital remapping number. However, since no one is used to tuning to 1, it wouldn't be very desirable. 70-99 don't have that problem since cable regularly uses them. I think there's a PBS somewhere (Michigan? Minnesota?) that maps to 99.


>
>
> :eek:)
>
 
> Could they remapped with all of
> ABC stations on Channel 2,
> CBS on channel 3,
> NBC on Channel 4,
> FOX on Channel 5,
> WB on Channel 6,
> UPN on CHannel 7,
> PBS on Channel 8,
> I on CHannel 9,
> Univision on CHannel 10,
> Telemundo on CHannel 11,
> Telefutra on Channel 12,
> TBN on Channel 13,
> Daystar on Channel 14,
> anything else on channel 15 and beyond?
---------
It could be done, but then you've got issues with stations with dual affiliations, and multiple stations with the same affiliation in the same market (this is more common with PBS). In theory it is a good idea.<P ID="signature">______________
From WNBC-TV New York this is Liiiiive at Fiiiiive!</P>
 
> Actually, the system allows stations choose any number
> between 1 and 99 for their digital remapping number.
> However, since no one is used to tuning to 1, it wouldn't be
> very desirable. 70-99 don't have that problem since cable
> regularly uses them. I think there's a PBS somewhere
> (Michigan? Minnesota?) that maps to 99.

Before PSIP was mandatory, several PBS stations directly fed the PBS-HD stream off the satellite and for this reason the station would remap to 80-3, as that was the number fed with the stream off the satellite. I think KRMA in Denver did this.

WXII in Winston-Salem, NC went without PSIP for a long time and people with certain boxes were only able to scan for and decode the channel during primetime HD from the network, when it remapped to 81-1, which, as with PBS, was fed off the satellite.

I seem to recall hearing that WB programming is fed as 75-1 off the satellite, but I can't say for sure.

I'd love to know what the other networks remap to off the satellite.

- Trip<P ID="signature">______________
Visit my website, www.rabbitears.info! It's eventually going to be your one resource for television info! Digital television, histories, and technical information for the entire USA from one source!</P>
 
> In theory it is a good idea.

In practice, it's a terrible idea.

You want to be the regulator who goes into Buffalo and tries to tell ABC affiliate WKBW (channel 7), CBS affiliate WIVB (channel 4) and NBC affiliate WGRZ (channel 2), each of which has spent half a century or more building a brand identity in the market, that henceforth DTV viewers will see WKBW on channel 2, WGRZ on channel 4 and WIVB on channel 3? At the same time as analog viewers still see WKBW on 7, WGRZ on 2 and WIVB on 4?

And then what do you do if you're in Batavia, halfway between Buffalo and Rochester, with a DTV tuner trying to remap both WIVB and Rochester's WROC to 3, WKBW and Rochester's WHAM to 2, and so on?

And what happens to a local station that's built a strong brand identity, then goes through an affiliation swap? Think they'd be happy about having to change virtual "channel" number, too?

Nah, me neither...

(I should note here that the idea of mapping channel number to network does have a place - in other countries that have national networks. In Taiwan, which has adopted the same ATSC DTV system used in North America, the various networks are indeed mapping each of their transmitters to "1," "2," "3," etc. It's not unreasonable to think that some of the Canadian provincial networks may do the same sort of remapping down the road, with all Global/Ontario transmitters mapping to 3, TVO to 13, and so on. Even there, though, there's the prospect of conflict with other established brands on those channels.

And in the US, the ATSC system has provisions for the use of virtual channels 70-99 for networked subchannels. Tribune, for instance, has reserved "75" in each market where it operates, so it could someday launch some sort of "Channel 75" service that would actually ride on subchannels of WPIX-DT, WLVI-DT, WGN-DT and so on.

But the established networks have decades of history of being branded with different channel numbers from market to market, and the industry has spoken - strongly - in favor of maintaining that system.)<P ID="signature">______________
Tower Site Calendar 2006 JUST RELEASED! - <a target="_blank" href=http://www.fybush.com/nerw.html#calendar>www.fybush.com</a></P>
 
> I have asked this before but never received an answer:
> Let's take the case of WFMY, analog 2, digital 51, in
> Greensboro, NC. True, they plug the fact that their
> regular schedule is on 2-1, while a 24-hour news and
> weather service is on 2-2. What I want to know is,
> how much difficulty would a viewer in, say, Danville, VA,
> 50 miles away, have pulling in WFMY-DT, even with a UHF
> antenna?

If WFMY-DT is running full power from the same site it's using for analog, it should be receivable at about the same level as analog in Danville.

The subchannels are irrelevant in this case; that just tells you how WFMY-DT divides up the data stream it sends out. If you can get that data stream (and that's all DTV is, a constant 19.39 mbps stream of data), you can get whatever subchannels it contains.

> I do know where the Big Four affiliates in Atlanta will be:
>
> WSB (ABC) analog 2, digital 39
> WAGA (Fox) analog 5, digital 27
> WXIA (NBC) analog 11, digital 10
> WGCL (CBS) analog 46, digital 19
>
> How difficult will it be to receive these in Athens,
> 70 miles away?

Again, it depends on whether they're running full power or not.

I'm about 70 miles from the transmitters of the Buffalo stations. The same stations that come in best for analog reception lock in with a nice strong DTV signal.

(I'm also using a good directional UHF antenna, mounted up high above the roof with a rotor and a preamp.)

There are other stations in Buffalo that are running considerably less than full power. Those don't come in here; neither do the stations (analog or digital) using Grand Island as a transmitter site, because of terrain blockage between that site and my receive location.

There's an added complication of co-channel interference, of course - if you're trying to receive an out-of-market DTV signal and you're suffering interference from an out-of-market analog signal on the same channel in the other direction, you'll have problems.

But in general, DTV coverage is supposed to closely replicate current analog coverage. There are still some markets that have yet to build out to full power, generally for tower-siting reasons, but most of the country is now past the so-called replication deadline, and most of the "big 4" affiliates around the country are supposed to be at maximum power now. <P ID="signature">______________
Tower Site Calendar 2006 JUST RELEASED! - <a target="_blank" href=http://www.fybush.com/nerw.html#calendar>www.fybush.com</a></P>
 
> > The whole thing's designed to be as transparent as
> possible
> > to the casual viewer.
>
> For the most part you're correct. I can foresee one minor
> exception where the change won't be so transparent:
> Scranton/Wilkes-Barre. They've always been a UHF-only
> market but WBRE and WYOU are going to stay with their DTV
> allocations of 11 and 13, respectively. Although the market
> was ranked by Nielsen in 2000 as top-10 in cable penetration
> with 82%, anecdotal evidence suggests that a lot of people
> are still getting their TV off the air, especially in
> Wilkes-Barre, where most of the broadcast towers are
> located, and where the cable company has a very bad
> reputation. The area also has a very high percentage of
> poor and elderly residents.
>
> So here's the problem: Granny has two UHF antennas attached
> to her chimney so she can get all of the stations. Now
> you're telling her that she also needs a VHF antenna to get
> channels 22 and 28, which aren't even VHF as far as she's
> concerned.
>
Would WBRE, WYOU, and other stations whose digital channels have considerably lower numbers than their analog channels be able to forego mapping to their analog channels and instead rebuild their brand identities around their digital channels, by any chance? Even today, when over 80% of US television households have cable or satellite and the average TV set has long since passed the days of having separate VHF and UHF tuning knobs, many of us still tend to think more highly of lower channel numbers, as irrational as that may be. Thus, the initial confusion that would stem from such cases as WBRE and WYOU associating themselves with their respective digital channels or, to provide a Top-10-market example, Atlanta's WGCL "upgrading" its brand identity from "CBS 46" to "CBS 19" might be more than made up by a higher perception of prestige among viewers. "Hey, Channel 28 is now Channel 11! They're really moving on up!" It's definitely crazy, if not stupid, but that seems to be how at least some of our friends and/or neighbors think.

Also, what about stations that prefer to brand themselves by their most common cable channel numbers, like San Diego's KSWB "WB 5" or Charlotte's WCNC "NBC 6"? Would those stations have the freedom to map their digital OTA signals to their predominant cable channel numbers, since their analog OTA channels might not be very familiar to most of their viewers?

In both of the above situations, it would be quite a shame if the FCC insists that even those stations map to their analog OTA channels.<P ID="signature">______________
This is AirwaveSurfer, reminding you that portions of this post have been prerecorded.</P>
 
> Could they remapped with all of
> ABC stations on Channel 2,
> CBS on channel 3,
> NBC on Channel 4,
> FOX on Channel 5,
> WB on Channel 6,
> UPN on CHannel 7,
> PBS on Channel 8,
> I on CHannel 9,
> Univision on CHannel 10,
> Telemundo on CHannel 11,
> Telefutra on Channel 12,
> TBN on Channel 13,
> Daystar on Channel 14,
> anything else on channel 15 and beyond?
>

What would you do in DMA's like Boston and Tampa Bay which have two ABC affiliates?
 
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