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Discussion Starter · #1 ·
Today my cable box was shut down, so I hooked the direct cable line into my tv direct


I could not believe how much better my SD picture was!

It was shocking, When my box was turned back on and running the feed into my tv the picture was worse again


It seems that when the cable box is NOT used I get a much better picture, too bad i cant get HD like this, Because i bet it too would look better



Can anyone explain this?
 

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It's simple - the cable box tuner is not on par with many TV tuners.


I found this out 15 years ago in a comparison between my Sony XBR's tuner and the one inside a Scientific Atlanta. Sony's won hands down, but from a services standpoint I was forced to put the box back in the chain.


It seems as if nothing really has changed.


Many people have reported that using a cableCard instead on the cable company supplied box results in superier picture.


-AJ1
 

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Quote:
Originally Posted by CounterInsurgent
PQ quality consideration.... Cable box’s ruin PQ!
They certainly don’t do anything to improve picture quality.

Audioholics.com: “CableCARDs - A Primerâ€


“The HUGE advantage comes in the picture quality. For those of you under the impression that the local cable company cares about quality and such things as accurate scaling, you are sorely mistaken. Local cable companies charge a small monthly fee (and usually no installation fee) for those utilizing their equipment. What this means is that they are concerned about features but certainly not about quality, since most of their customers are not aware of what they are missing.

CableCARDs allow the user to decrypt digital cable and use higher quality components to handle scaling and display of the cable channels.


Mitsubishi showed off two televisions displaying standard definition cable channels side by side at the 2004 CEDIA Expo. One unit was displaying digital cable via a provided set-top box, the other was using CableCARD. The difference was astounding. The Mitsubishi’s integrated scaler was of so much higher quality then the one provided by the cheap set-top cable box that clarity was improved, ghosting was dramatically reduced and (real) edge detail was preserved - so much so, that I wondered how I was conned into thinking that it was simply broadcast that way to begin with. THIS is why CableCARD is such a significant development.â€
 

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Well i have a Motorola 6412 DVR and i have to use it for the digital/HD channels, the SD channels look like crap, my older motorola digital box looked fine.

I use a splitter behind the set, so when i watch any channel lower than 100 i use direct cable and my panny PA25's tuner.
 

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If you're comparing the RF analog output of the box (NTSC) to direct cable's RF NTSC, signals should appear similar. The box output might involve a simple amplifier that shouldn't make the two signals drastically different.


A comparison of the direct cable's NTSC signals, each analog channel occupying about 6 MHz, with digital channels might reveal too much compression by your cable head end or a supplier of complete head-end program 'packages'. Head ends may squeeze 8 or more channels into each 6-MHz-wide cable slot, so too many channels per slot can make video appear fuzzy from lack of bandwidth. (MPEG-2 compression 'tosses out' finer details to achieve the desired compression; that's unless adequate detail for the bandwidth has been prefiltered already.)


A few times I've seen direct-cable sources, or the same channel over the air, look better than digital cable or analog cable through converters. More often digital cable (SD) has a slight edge because the video noise is less and images are generally crisper. It's a tedious process, but using a converter's diagnostic mode lets you map how many channels/sources are assigned to each cable frequency. Digital cable employs statistical multiplexing, shifting bit rates as needed depending on motion and detail within many video channels.


Mixing in H/DTV sources with SD complicates comparisons. If one channel looks dramatically better at one cable-channel location than another, it could be you're comparing a source that has been upconverted from 480i to 1080i or 720p with the original 480i channel. Locally, for example, Time Warner Cable delivers an analog (SD) CBS, a digital (SD) CBS, and a upconverted 480i-to-1080i (H/DTV) CBS (or true 1080i, mostly during primetime). -- John
 

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Unfortunately that is the only real disadvantage to CableCard use. Once directly connected to the set for descrambling, you cannot record digital channels. Boxes, on the other hand, usually provide multiple output connections. I already have 2 standalone recorders in the house but with this setup my reception may be the best it can be but recording is still strictly limited to analog channels. I'm no worse off than I was before the CableCard install but it's frustrating to see so much better quality feed even with non-HD digital and not be able to record it. At least the analogs enjoy the benefit of direct cable connection and not the PQ destroying cable box pathway. I have yet to use any box which did not degrade PQ when compared to direct connection.


Of course I could always use both the CableCard for set viewing and an HD box rental for recording on the split line. But that way would still only record the digital non-HD channels. To record HD an HD DVR is a must. As I hate using Cable Co. equipment I'm still a waitin'.
 

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Quote:
Originally Posted by CounterInsurgent
Today my cable box was shut down, so I hooked the direct cable line into my tv direct


I could not believe how much better my SD picture was!

It was shocking, When my box was turned back on and running the feed into my tv the picture was worse again


It seems that when the cable box is NOT used I get a much better picture, too bad i cant get HD like this, Because i bet it too would look better



Can anyone explain this?
Being on this forum this might be a correct guess that simply explains this....(not taking away from John Mason's posts...but man is that English?)

Are you comparing SD from the cable box through component cables and SD with a direct RF connection.?

Try RF out of the box (or composite (yellow), components really mess up an analog signal.
 

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My SD looks horrible no matter what I hook it up too. Some of it is just the channel. TNT looks downright horrid, but USA looks great. Discovery in HD is simply incredible.


Try getting a new cable box. The newer models are a little better at scaling.
 

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Quote:
Originally Posted by John Mason
If you're comparing the RF analog output of the box (NTSC) to direct cable's RF NTSC, signals should appear similar. The box output might involve a simple amplifier that shouldn't make the two signals drastically different.


A few times I've seen direct-cable sources, or the same channel over the air, look better than digital cable or analog cable through converters. More often digital cable (SD) has a slight edge because the video noise is less and images are generally crisper.
This not entirely true. There are many STBs which streamline their internal systems and convert the analog cable into digital mpg before displaying. The mpg encoder has been reported to be not to good on many boxes, leading to more artifacts for analog cable channels when compared to connecting analog cable directly to TV. Further, the scaler on some of these STBs is not too good, so if you have the STB configured to output 1080i or 720p, the 480i stuff looks bad. Sometime the STBs provide a 480i passthrough so you can use your TV scaler.


Re: the SD digital channels, they can look better or worse than analog. Some of the SD digital channels use a frame size that has reduced resolution. It looks ok on 4:3 television, but if you stretch to 16:9 it looks horrible. If the frame size is reasonable and the bitrate is high, then SD digital does look better than analog.
 

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Discussion Starter · #11 ·
however, i have noticed that every box the comcast company kicks out..... sucks.


The first one was SLOW to respond, it was like tech from the 1980's


This newer DVR/hdtv box is buggy too.... microsoft go figure..... sometimes when i hit FF, it doesnt stop, it FF threw the whole show, then i need to start it over


Or it claims to record a whole show, but only records the first 1 min of it


This is the THIRD box ive had replaced, and while they are fine for 3 months, after that they go down hill..... its the sadest thing i have ever seen
 

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The digital cable boxes have to convert SD analog channels to digital and the HD boxes upconvert it adding a lot of artifacts. One way to improve PQ on the analog cable channels is to use a simple 2way RF splitter and feed both your TV's analog tuner and the HD box. Then use the TV's analog tuner for the analog channels and the box only for digital/HD channels.
 

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Quote:
Originally Posted by agogley
optivity,


Only the most recent (i.e. within the last 12 months or so) displays have cable card abilities. I have a Pio 910...no cable card.
Sorry, a CableCARD is only an option for CATV subscribers with DCR TVs.


I purchased (2) HD TV's during the past five years (Panasonic CT-36HL42 - 2001 & Panasonic TH-50PX50U - May 05) each performs well but lacks at least one additional feature I'd like to have... maybe my next TV (65" SED) will do it all. :)
 

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Quote:
Originally Posted by optivity
Sorry, a CableCARD is only an option for CATV subscribers with DCR TVs.


I purchased (2) HD TV's during the past five years (Panasonic CT-36HL42 - 2001 & Panasonic TH-50PX50U - May 05) each performs well but lacks at least one additional feature I'd like to have... maybe my next TV (65" SED) will do it all. :)


That was really my point. Only sets in the last year or so have been DCR. I bought my Pio 910 only a few months before the DCR 920. I might have waited if I knew that. But, oh well...I still use DVR now anyways.
 

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Quote:
Originally Posted by agogley
That was really my point. Only sets in the last year or so have been DCR. I bought my Pio 910 only a few months before the DCR 920. I might have waited if I knew that. But, oh well...I still use DVR now anyways.
Agreed. We have to work with the technology we purchased. My CRT-TV is HD-ready and requires an external STB to receive HDTV. I'd like to lease an SA8300HD-DVR from Albany Time Warner for the TV but refuse to do so until they change their "copy never" protection policies with the CableCARD to "copy once" which will enable Dolby Digital sound output to my Onkyo receiver.


The CATV provider's "copy protection" policies has resulted in a 33% decrease in services I formally subscribed to.
 

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Quote:
Originally Posted by agogley
I too am peeved with Cable. always raising prices for worse service.
This is because the synonym for Cable Provider is spelled: M-O-N-O-P-O-L-Y
 
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