Selective Channel Degredation: Fine Tuning?

[John Colburn]

I am recording CATV under XP Prof OS.

Main CATV signal is split to my regular TV set and then by splitter lead, preamplified, running an additional 25 ft of quad shielded coax premium cable to server. When the 25 foot cable reaches the location of my server, the signal is again split with one 6 foot quad shielded cable as input to a Magnavox monitor (has built-in tuner) and the second 6 foot split running to the server which houses the twin tuner PCI Card (Hauppage/500 from the currently sold Sage Bundle).

The signal at the upstream regular TV set (after the first splitter), and the Magavox monitor with its own built-in tuner receiver (after the second splitter) are great, but the video shown on the same Magnavox monitor (VGA input) from Sage TV is terrible on some channels (very snowy), and the resulting recordings are the same (even @ 3GB/hr). Other channels are fine when viewed or recorded. Recordings are also played back on same upstream TV via wireless H. Media Server, confirming the quality disparity of some channels.

My questions are:

(1) Is this a driver problem for the tuner card?,
(2) A decoder problem?
(3) Is there a registry channel definiton problem?
Can the channel definition be edited for tuning?
(4) Is there some type of interaction between my video card in the PC that is limiting the resolution?

Frankly, this looks like a failure in the AFC circuits in the tuner, or simply being a skosh off on the frequency needed for the quality of my cable signal. Perhaps a slight sideband shift?

Yes, picture quality varies around the house depending on the TV set and its cable wiring, but I have gone to a lot of trouble to be sure I have quality signal delivered to this recording setup.

This, I believe, is a problem in my Sage setup, or the "adjustment" of particular components that are in my system.

Any suggestions for tweaking?

John

[Opus4]

Perhaps there is enough signal loss to cause problems -- I think you said you had an amp, but depending on its placement with all those splits, you may not have an optimal signal at some connections, or else the tuners aren't sensitive enough & need a stronger signal anyway. I may have read too fast, but did you try connecting a TV in the same place where the tuner is connected? Or, perhaps try removing a split or temporarily to see how that affects it.

- Andy