S-Video problems on new 55H70 (1 Viewer)

[Sujeet Patel]

I just took delivery of my Toshiba 55H70 today, and have a quick question.
I've gathered through this forum that standard cable TV doesn't always look the greatest on TVs like this, as it tends to magnify the irregularies. So I ordered Digital Cable, and got a 12ft S-Video cable (from Radio Shack, was
in a hurry) since the general consensus is that the picture will be better with S-Video vs. Coax.
With the S-Video input, there is alot of grainyness, even my girlfriend IMMEDIATELY noticed it. It happens on every channel. If I use the coax video out, it looks crystal clear, whether I go through the set-top or if I plug it into the TV directly.
Any ideas why this is happening? I'm assuming one of 3 things:
1) Bad set-top s-video out port
2) Bad s-video cable (does brand really matter?)
3) Bad s-video input ports on the TV (but I tried both of them).
Let me know, as I'll probably just get rid of the set-top if I can't resolve this, the only reason I got it was for the clearer & sharper picture through s-video. Thanks.

 

[PeterG]

The reason why the S-Video out looks poor compared to RF (or composite) is that all the digital cables boxes (whether made by General Instrument/Motorola or Scientific Atlanta) have extremely rudimentary Y/C separation, analogous to a really cheap glass comb filter.
It would be preferable for you to use the composite output of the box as with the RF output you will get only mono audio.
However, what I have said holds for the analog channels as the digital channels are transmitted in an MPEG2 bitstream and when decoded the signal is in component form.
So, normally, you will get superior performance on analog channels with the composite output (whereupon you will be using the 3-D comb filter of your TV)whereas with the digital channels S-Video should be better.
Peter
------------------

 

[Sujeet Patel]

Thanks, that clears things up immensely. Since I don't really watch any of the digital stations anyway (they're nice but not necessary), I'll probably drop the digital service and pocket the $10 extra a month. I only got digital cable because I was concerned about the quality of regular cable on this TV, which has proved to be a non-issue for me. Thanks again.