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Discussion Starter · #1 ·
Hi all. Kind of new to the HT world so please bear with me.


I think this is the right forum for this question.


My question is regarding my TV reception. And I'm wondering if my setup may be wrong.


I have a Panasonic 53" widescreen HD TV, a Yamaha 5760 receiver, and a Motorola HD cable box.


Connection #1: I have the coaxial cable from the wall connected into the cable box then directly to the tv's coaxial cable tv input. (labeled AUX on the back of the TV)


Connection #2: I also have the cable box connected directly to the tv via component #1 (rgb) with a digital coaxial audio connection fron the cable box to the receiver.


My question: Why is the cable picture better using the coaxial tv connection than when I switch to component 1 using the RGB?


Clear as mud?


Thanks


Mediccc24
 

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Quote:
My question: Why is the cable picture better using the coaxial tv connection than when I switch to component 1 using the RGB?
For several reasons:
  1. The TV has a built-in 3D comb filter that it uses [only] on SD channels input through coax. This 3D comb filter helps to clear / smooth analog channels. When you use component, you bypass this filter.
  2. The electronics in the Motorola do not do as good a job with the SD scaling / upconversion as the electronics inside the TV.

Something you might want to try...


Turn your Motorola STB off. Press Menu. From the configuration screen, make sure HDTV output is set to 16:9 1080i. Enable the option that says bypass mode and set it to 480i. That will output SD channels without any upconversion, which would at least eliminate item #2 above.
 

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Discussion Starter · #3 ·
OK, so if I follow you, the comb filter is not used on HD channels (assuming SD stands for Standard Definition?) input through coax. So, HD channels should look as good through coax as through component?


Not too clear on the upconversion stuff, but I do notice that the HD programming totally fills the screen in component but leaves a black border when using coax.


So, after I make the 480i change you suggest, under what circumstances would it be best to view through coax and through component?


Thanks much
 

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OK, so if I follow you, the comb filter is not used on HD channels (assuming SD stands for Standard Definition?) input through coax. So, HD channels should look as good through coax as through component?
SD refers to standard definition (480i).


You can't get HDTV through the coax output, only HD that is downconverted to SD -- unless it's a passthrough/bypass coax output and you have an integrated HDTV with a built-in CableCard/QAM tuner.

In the future, when posting to an AVS forum, include the specific make and model of any equipment (TV, cable box, etc) that relates to your questions. It makes it more difficult to provide answers when you don't.

Quote:
So, after I make the 480i change you suggest, under what circumstances would it be best to view through coax and through component?
Compare the two. Coax will probably still be better for SD, but switching to 480i on cable box may improve SD so it is close enough to coax that you don't feel the need to switch. Switching inputs is a hassle, after all.


Once again, you can't get HDTV through coax (unless your set is a CableCard/QAM model). You must use component or DVI for HDTV.
 
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