Poor Picture Quality on Analog signals

[vernvan]

I just got Adelphia cable with HDTV using the Scientific-Atlanta 3250HD stb. The first thing my wife and I noticed (after noticing the great HD picture) was that the picture quality on the analog signals was much worse than our old directv picture. Since my monitor has 5 inputs, I made good use of them. From the stb I hooked up s-video, composite and rf in addition to the component cable that Adelphia hooked up. I got the following results:

Component: noisy
S-video: noisy
Composite: clean
Rf: clean

By noisy, I mean slightly. For example, solid colors will have some flickering/movement in them. Text will have slightly more artifacts around it. I have had a technician out twice and they changed out component cables and looked at the picture. Finally, they went back to the shop and after comparing feeds found that they have the same problem on the stb's in the shop. They said that they will be looking in to it. Probably means I'm screwed.

Does anyone have any experience with this? I have been told that this is happening because the comb filter in my tv is better than the comb filter in the stb. But if that is true, than the comb filter in the stb seems to be worse than the comb filter in all tv's.

Help me. I am tired of changing inputs when I change between analog and HD.

Vern :(

[HDTVBob]

Vernvan,
Although I am on Comcast and have a Motorola box, I had exactly the same problem. Comcast admitted there was a problem with the box software and they would have a fix shortly. However, what improved the analog picture was to split the cable feed between the STB and the cable coax input on my TV. If I want to watch analog channels, I simply switch the input from video to cable and get a better picture. Try bypassing the STB and run coax into the back of your set to see if you get a better picture this way. All you need to do this is a 2-way splitter and a couple of short coax cables and you should be able to switch signals with your remote and not have to get behind the set and manually change inputs.

[Blaster]

I didn't understand vern's till I read Bob's. I agree with HDTVBob. Split your incoming
signal BEFORE stb,then send standard cable to RF (coax) conn on back of TV. Then
use stb like say a dvd player,and hook it to TV via Y,Pb,Pr cable. Then using remote
just change inputs to what ever device you chose to view.

This is how I do it,and TV tuner performs MUCH better showing SD Cable
than my stb shows SD Cable.

:)

[techstar25]

This happened to me. The reason why this happens is because your STB is set up to output 1080i through the component outputs, and 480i through the composite and coax. The analog tv signal is natively 480i, and the HD signal is natively 1080i. The problem with using only the component outputs is that your STB upconverts the analog tv signal to 1080i when it's sent through the component cable. Generally upconverted analog tv looks bad. What I did is just connect the component outputs from the STB to "Video 1" on my tv which receives the 1080i signal, and the composite output from the STB to "Video 2" on my TV which receives the 480i signal. Most of the time I can leave it on Video 2, which makes all channels look like a good 480i. When I want to watch a special HD show I change to Video 2.
The only reason why this is better than Blasters' suggestion is that you get both signals traveling through the STB so you can still get the channel guide onscreen no matter which video input you are watching.

[HDTVBob]

Techstar,
I like your idea but my Motorola HD PVR STB does not have any composite outputs; only component, S Video, coax RF and I believe DVI. This may be the case with others.

[summerfun]

Techstar,
I like your idea but my Motorola HD PVR STB does not have any composite outputs; only component, S Video, coax RF and I believe DVI. This may be the case with others.
In absence of composite outputs, use the s-video. Still no upconversion there.

[HDTVBob]

In absence of composite outputs, use the s-video. Still no upconversion there.

Dumb question, but S-Video is only for the video signal, correct? Then how do I get the audio to match up with it since I run all my sound through an A/V amp? Right now the audio comes from the cable coax connection directly to my HDTV and a set of composite audio cables back to the CD input on the A/V amp. With a S video cable from my STB directly to the HDTV would this accomplish the same thing and what I now have with the coax connection only set the HDTV to Video 1 or whatever? The reason I ask is I believe I can do something similar with my new small HDTV up in the kitchen where I have the same analog picture problem but not as bad because of the smaller screen.

[TimG1]

In absence of composite outputs, use the s-video. Still no upconversion there.

That's what I thought, but have you been able to get this to work with the SA8000HD? I tried it before on my box and didn't get a picture using S-Video. When I consulted the online manual, it said:


The S-Video Out connection is active only if the
8000HD has been set up to be in standard definition
only mode.

Perhaps I was doing something wrong. :headscrat I guess I'll try again tonight.

[Blaster]

all good remedies but the reason I split BEFORE stb,
then send to coax conn on back of TV
is that way I get good SD PQ (let TV do the work)
but , that way I can use Split Screen (PIP). It doesn't work if you go thru stb , does it ?

this is one thing that SD Cable has the advantage no other can touch...

[summerfun]

Dumb question, but S-Video is only for the video signal, correct? Then how do I get the audio to match up with it since I run all my sound through an A/V amp? Right now the audio comes from the cable coax connection directly to my HDTV and a set of composite audio cables back to the CD input on the A/V amp. With a S video cable from my STB directly to the HDTV would this accomplish the same thing and what I now have with the coax connection only set the HDTV to Video 1 or whatever? The reason I ask is I believe I can do something similar with my new small HDTV up in the kitchen where I have the same analog picture problem but not as bad because of the smaller screen.
If your S-Video is active (I don't know if it is or not) then you will run audio directly to your A/V receiver and the s-video directly to the HDTV for analog channels and component cables directly to the HDTV for the HD channels. There will be no cable going directly to the HDTV, only to the STB. You still have to change inputs to watch analog channels, but you can use all the benefits of digital TV guide, DVR and other digital features that you do not get with a direct connect cable.

If your S-Video is not active, then the set up you have is best.

IMO I have all channels go through the DVR STB even though the analog is lower quality because I like to use the DVR and digital features for ALL channels.

[vernvan]

1) S-video will give you pretty much the same picture on analog channels as component afterall, s-video is "component" (broken up into channels). If you note the first post, I get the same noisy picture with s-video.

2) The Scientific-Atlanta 3250HD stb has component, s-video, compostite and rf outputs, so I have configured it as stated before, to use composite 90% of the time and component when watching HD. Just a pain to change it.

3) I think that the only transparent solution is to have all digital cable, ie low resolution stations in SD. So, I am stuck with a work around solution until Adelphia upgrades.