Hd in USA - help me with my homework

amstrad

Member
Feb 27, 2006
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Hi.
First sorry for my broken english.
I must write a homework about hd telewison in USA.

I found many materials but need your help - can anyone do a some photos of hd channels , hd receivers. (directv and dish network )

I also don't know - do you have vod ? in Poland operator send a 30 movies in month to hard disk of digital receivers (push vod).We pay about 10$ for this.

This is very important for me.

i give my email adress : bid6@o2.pl

Thanks.
 

KyDave

Supporting Founder
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Dec 3, 2003
675
7
Kentucky
Here is a little help.

Dish Network HD receiver pictures. The common ones in use now are the vip211 and the vip622.

DirecTV HD receiver pictures

Satellite VOD is not quite as good as cable VOD (at least not yet.)

With Dish Network, my vip622 currently has 12 movies downloaded to the receiver available for viewing (push VOD as you said). $4.99 per movie. This compares to paying $3.99 for the same movie with regular PPV (Pay Per View - not on demand) - where a movie might start every half hour or so. They will also soon use an internet connection to expand what is available with VOD. Not sure just how 'on demand' this will actually be (might have to wait a little bit for the program to start).

Can't really comment on VOD with DirecTV.

Sounds like a fun assignment. Good luck!
 

navychop

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Here's a few facts:

The U.S. is one of the few countries in the world to use 8-VSB instead of COFDM modulation for OTA (over the air) digital TV. The later offers more redundancy and is generally used where 8 MHz of bandwidth is available, and works better with moving vehicles. 8VSB is generally used in 6 MHz of bandwidth and allows for some extra information or features and relies upon improvements in tuners to deliver pictures in less favorable conditions (such as multipath). And some state "...that 8-VSB offers a number of advantages over COFDM for broadcast DTV service, including superior overall coverage, lower costs of construction and operation, and immunity to impulse noise from household appliances." See the bottom article here if you want more info.

(The U.S. is the only country in the world that will continue the use of the VHF band for television after the analog transmissions are ended and digital transmissions take over. The rest of the world has moved OTA digital television to the UHF band exclusively.) Disregard- incorrect. See following posts. Should read "The U.S. is one of the very few....."

The old analog OTA TV system in the U.S. was called NTSC. The new digital OTA TV system is called ATSC.

The U.S. generally uses 60 Hz refresh rates while most/all of Europe uses 50 Hz.

The FCC (Federal Communications Commission) has established the below table for digital TV in the U.S. - called "Table 3" :

ATSC Table 3 Formats for DTV Transmission

Vert----------horz---------aspect----------fps/scan
1080----------1920----------16:9--------24p, 30p, 30i
720-----------1280----------16:9--------24p, 30p, 60p
480------------704----------16:9--------24p, 30p, 30i, 60p
480------------704-----------4:3---------24p, 30p, 30i, 60p
480------------640-----------4:3---------24p, 30p, 30i, 60p

Note that only the top two lines are referred to as "HD" - the rest are "SD" or "ED." HD is a subset of digital TV.

It is common in the U.S., at least, for the "1920" to be reduced to only 1440 or 1280.

Keep in mind about interlacing, and that in theory at least, 720 60p will display motion such as sports better than 1080 30i. But many other factors affect this.
 
Last edited:

ozeyeo

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May 7, 2004
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In reference to the transition to digital television, the U.S. is not the only country to use the VHF spectrum post closure of the analogue system. Australia's four major networks are all staying in the high VHF spectrum.
 

navychop

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I'll have to check that out. I've read otherwise, but certainly not everything published is accurate.

Might want to leave that part out of your presentation. ;)
 

navychop

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Well, that was interesting reading. Kind of messy, the way Australia added more TV channels, then even the whole UHF band, over the years.

It is certainly true that Australia will use the higher part of the VHF band for digital TV, though I cannot determine if it's channels 6 thru 12 or just 11 & 12. I gave up reading. So it may well be that other countries will use VHF also.

Thank you for the correction, I will correct my earlier post.
 

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