# HD off-the-air



## Tristateviewer (May 11, 2008)

Can someone tell me if you pick up an off-air channel signal out of your market area via your off-air antenna that is being broadcast in high definition why that signal does not come in high definition? Do you have to be within a certain mileage to the broadcasting tower to receive the signal in high definition?


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## scooper (Apr 22, 2002)

As long as your reception device can receive it, you CAN get it in HD. The next thing is your reception device output in HD or is it only standard Definition ?

Now the real question is - are you watching the Digital version of the channel or the analog version ?

Specifics on what channel you're talking about and your location would help out alot.


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## Upstream (Jul 4, 2006)

TSV --

I'm not sure I understand your problem. If you are receiving the HD channel, it will be HD.

For example, let's say you are trying to receive channels from NYC.

If you tune to analog channel 5, you will get the analog SD signal for WNYW.

If you tune to digital channel 5.1, you will get the HD version of WNYW. You either receive it (in HD) or you don't receive it at all.

If you tune to digital channel 5.2, you will receive that digital channel. But since 5.2 is a SD digital channel, you will see an SD picture, not an HD picture.


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## Tristateviewer (May 11, 2008)

Upstream said:


> TSV --
> 
> I'm not sure I understand your problem. If you are receiving the HD channel, it will be HD.
> 
> ...


I can receive channel 3.1 from Hartford, CT WFSB in high def via OTA. I can also receive 3.2 from Springfield, MA via OTA but it never comes in high def. Both stations are CBS network stations. When CBS is broadcasting something in high def, I receive the HD signal via OTA in high def but I do not receive the Springfield, MA station 3.2 in high def when I know it is being broadcast in HDTV. What is that all about?


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## Kansas Zephyr (Jun 30, 2007)

Most stations use x.1 as the "primary channel", including HD, and x.2, x.3, etc. as SD digital sub-channels.

Are you sure that the station in question is offering HD service on x.2?

Also, not all digital TV stations pass the network's HD broadcasts.


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## Stewart Vernon (Jan 7, 2005)

Tristateviewer said:


> I can receive channel 3.1 from Hartford, CT WFSB in high def via OTA. I can also receive 3.2 from Springfield, MA via OTA but it never comes in high def. Both stations are CBS network stations. When CBS is broadcasting something in high def, I receive the HD signal via OTA in high def but I do not receive the Springfield, MA station 3.2 in high def when I know it is being broadcast in HDTV. What is that all about?


Given the bandwidth limitations per channel, I have not heard of any OTA broadcaster multicasting more than 1 HD channel per alotment.

In other words... IF 3.1 is in HD, I would be extremely surprised to see 3.2 also in HD unless it was really crappy compressed HD because the bandwidth just isn't there to do it.


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## Tower Guy (Jul 27, 2005)

Tristateviewer said:


> I can receive channel 3.1 from Hartford, CT WFSB in high def via OTA. I can also receive 3.2 from Springfield, MA via OTA but it never comes in high def. Both stations are CBS network stations. When CBS is broadcasting something in high def, I receive the HD signal via OTA in high def but I do not receive the Springfield, MA station 3.2 in high def when I know it is being broadcast in HDTV. What is that all about?


WFSB 3.2 is not in HD.

I believe that they feed the Springfield cable system in HD via fiber.


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## Tony Chick (Aug 24, 2006)

HDMe said:


> Given the bandwidth limitations per channel, I have not heard of any OTA broadcaster multicasting more than 1 HD channel per alotment.
> 
> In other words... IF 3.1 is in HD, I would be extremely surprised to see 3.2 also in HD unless it was really crappy compressed HD because the bandwidth just isn't there to do it.


Several of my Los Angeles locals do just that, some do 1 HD + 2 SD and a couple even squeeze 3 SDs in there. All due to compression and dynamic bandwidth allocation. You do see some breakup when there is a lot of visual action on the HD channel and there isn't quite enough bandwidth.


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## Jim5506 (Jun 7, 2004)

I do believe I read a post somewhere about a station in Oklahoma that had a new generation of encoder and was broadcasting two HD signals on the same channel.


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## scooper (Apr 22, 2002)

Only if each HD channel is a 720p.... Otherwise there is not sufficient bits.


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## Stewart Vernon (Jan 7, 2005)

Tony Chick said:


> Several of my Los Angeles locals do just that, some do 1 HD + 2 SD and a couple even squeeze 3 SDs in there. All due to compression and dynamic bandwidth allocation. You do see some breakup when there is a lot of visual action on the HD channel and there isn't quite enough bandwidth.


But you don't see more than 1 HD channel in there. I have seen many variations of 1 HD + 2 SD, or +3 SD, or even +4 SD... but I've never seen 2 HD on the same OTA channel.


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## Stewart Vernon (Jan 7, 2005)

scooper said:


> Only if each HD channel is a 720p.... Otherwise there is not sufficient bits.


That's the only scenario I could see... if someone like ABC or FOX did it with 2 720p channels... but even then I bet the quality dip would be noticable enough to wish they weren't doing it. I have heard of some testing rumored around the country, but haven't heard of anyone actually doing it with their day-to-day programming as yet.


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## jclewter79 (Jan 8, 2008)

KXII out of Sherman TX broadcast CBS and FOX in HD at the same time. This is the Oklahoma channel mentioned it is actually primairly based in Sherman TX but, is only considered a local Channel in one TX county.


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## Jim5506 (Jun 7, 2004)

According to this story, they do a 1080i, a 720p and a 480p all on one 6 MHz channel.

http://broadcastengineering.com/hdtv/kxii-hd-sd-channel/


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## n3ntj (Dec 18, 2006)

Wow.. 2 HD and 1 SD in a 6 MHz slot? I wonder what the PQ of each looks like on each. Anyone in that area that can give us feedback?


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## scooper (Apr 22, 2002)

That would be PUSHING the limits, but I suppose it's doable - it would also depend on what programing is happening as well. DBS does this all the time (i.e. so many channels per transponder), so the idea isn't new - it's just the first time I've heard of someone packing it in OTA.


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## jclewter79 (Jan 8, 2008)

I really does not look that bad but, I do not watch it to much because my antenna is pointed south to get Dallas so I have to turn the antenna to get it. I have SD versions of the channels on E* and that is good enough for me. Besides the local CBS news on the channel is not in HD anyways so no real need to pick it up over the air, any of the HD shows can be picked up from dallas.


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## goldstar_media (May 9, 2008)

In one room, I have cable television without the box, just the cable wire directly going to the television. The television is old, it's not an HDTV. Will I need to pay the cable company for a digital box for that tv if I want my over-the-air stations next year?


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## machavez00 (Nov 2, 2006)

The TBN affiliate here in Phoenix is doing five SD channels


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## Kansas Zephyr (Jun 30, 2007)

goldstar_media said:


> In one room, I have cable television without the box, just the cable wire directly going to the television. The television is old, it's not an HDTV. Will I need to pay the cable company for a digital box for that tv if I want my over-the-air stations next year?


No.

As long as your cable company offers an analog "basic" package, you will need to do nothing.

They will downconvert the signal for you.


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## TheDurk (Mar 8, 2007)

Kansas Zephyr said:


> No.
> 
> As long as your cable company offers an analog "basic" package, you will need to do nothing.
> 
> They will downconvert the signal for you.


True--but many Cable Co's are moving to drop the analog services and requiring everyone to get an STB. I will bet that movement accelerates after the SD analog feeds are no longer available from the networks.


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