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  1. Member
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    The system that I have at home is a Dish Network High Definition Box hooked up to a Samsung 480P/1080i HD CRT TV. I'm trying to get my head around how this works.

    The cable that runs from my satellite to the Dish Network box carries a digital signal (1 and 0's), right?

    The only connection going from my satellite box to the TV is component. The same goes for the my DVD player. Component video is analog regardless if it is progressive or interlaced, correct? So the Dish Network is changing the signal to analog and then sending it along its way to my TV.

    Is a CRT HDTV really digital or is that a misnomer since it is getting a component signal and displaying it?

    For a standard TV signal being sent is my TV deinterlacing it and displaying it in the 480p format?
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  2. Member edDV's Avatar
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    Originally Posted by bsuska
    The system that I have at home is a Dish Network High Definition Box hooked up to a Samsung 480P/1080i HD CRT TV. I'm trying to get my head around how this works.

    The cable that runs from my satellite to the Dish Network box carries a digital signal (1 and 0's), right?
    No it is FM modulated analog RF


    Originally Posted by bsuska
    The only connection going from my satellite box to the TV is component. The same goes for the my DVD player. Component video is analog regardless if it is progressive or interlaced, correct?
    Yes YPbPr is analog but it is also can be HiDef (usually 1080i) depending on settings.


    Originally Posted by bsuska
    So the Dish Network is changing the signal to analog and then sending it along its way to my TV.
    Yes if you are using wideband YPbPr analog component connection. This is not bad.


    Originally Posted by bsuska
    Is a CRT HDTV really digital or is that a misnomer since it is getting a component signal and displaying it?
    A typical CRT HDTV will accept analog component YPbPr convert it to digital, then upscale to 1080i (unless it is 1080i), then display after processing as either 1080i or 480p or 540p* depending on remote settings. 1080i usually looks better as 1080i, DVD usually looks best as 480p, NTSC (normal channels) usually looks best as upscaled 1080i.


    Originally Posted by bsuska
    For a standard TV signal being sent is my TV deinterlacing it and displaying it in the 480p format?
    Normal CRT mode is to upscale it to 940i-1080i (with 3D comb filtering) depending on the TV. LCD will deintelace and scale to the native LCD resolution (800x600 to 1366x768 typ.). A CRT display will have a dot pitch that limits viewer resolution to between 800x600 to 1000x960. This has the result of removing NTSC dot crawl and making scan lines too small to see. (even if you look closely).
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  3. Member
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    Thank you for the superb answers.

    I've read a lot about digital technology and it seems that the goal is to keep things digital and stay away from conversion of analog to digital or vice versa because of degradation.

    It's interesting to me that in the first step (from dish to satellite box) it isn't even digital.

    You mentioned that my digital CRT TV converts it to digital and then upscales it. Do you know where in the TV this is happening? Does this mean that the signal gets converted to 1 and 0's at the ADC and then sent to the electron guns? If so, what is the advantage of this?

    Thanks again...
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  4. Member edDV's Avatar
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    Originally Posted by bsuska
    Thank you for the superb answers.

    I've read a lot about digital technology and it seems that the goal is to keep things digital and stay away from conversion of analog to digital or vice versa because of degradation.

    It's interesting to me that in the first step (from dish to satellite box) it isn't even digital.

    You mentioned that my digital CRT TV converts it to digital and then upscales it. Do you know where in the TV this is happening? Does this mean that the signal gets converted to 1 and 0's at the ADC and then sent to the electron guns? If so, what is the advantage of this?

    Thanks again...
    Transmission is always an analog process (e.g. RF over the air, RF sat uplinks/downlinks, cable RF distribution, magnetic tape recording) but modulation schemes can input digital streams and recover them through demodulation with very low data error rates. Analog componet cables can provide high quality HDTV. The quality is determined more by design implementation and the cost of parts used.

    A typical HDTV will accept analog and digital inputs, convert everything to digital and then process the signal to optimize for that particular display. The actual display process is usually analog again (e.g. RGB CRT, LCD panel drivers, Plasma's glowing gasses, DLP with spinning wheels and such). What matters is the resolution that reaches the screen after all the conversion.

    The picture quality issue is more complex than just resolution. The difference between a cheap set and an expensive set has more to do with the quality of the image processing and the quality of the display itself.
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