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#67488 - 07/06/06 05:12 PM Digital CATV
Redsy Offline
Registered: 03/28/01
Posts: 2056
Loc: Bucks County PA
The VDV areams slow so,I'll start here.
Feel free to relocate me

A single RG6 feed about 30' long into an attic. A 4-way Digital 2 gigahertz splitter. 4 taps off the splitter. One Digital box & TV won't work through the splitter, but does work with a direct inline coupling.
Would an ampilfier help?

I do this hook-up in new homes regularly with no problem, but I don't think I've ever encountered Digital CATV before.

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#67489 - 07/06/06 06:56 PM Re: Digital CATV
gfretwell Offline

Registered: 07/20/04
Posts: 9039
Loc: Estero,Fl,usa
This may be a 2 way connection that the balun in the splitter is not passing upstream.
Greg Fretwell
#67490 - 07/06/06 07:16 PM Re: Digital CATV
ExpressQuote Offline
Registered: 04/27/06
Posts: 83
Loc: BC, Canada
If it requires info as well as sends info, it many require a bi-directional splitter. The only ones that I have ever seen are amplified.

I know that this info is only worth about 2 cents. But hoping it might give you some direction.

#67491 - 07/06/06 08:08 PM Re: Digital CATV
e57 Offline
Registered: 05/27/03
Posts: 2876
Loc: S.F.,CA USA
The VDV area does seem slow, but often is frequented by people who are the most knowedgable about this type of thing. I can't say for sure, but have noticed some often dont pop up in other areas of the forums here, so it seems. But do keep a watchfull eye out there.

Anyway, the amount and quality of the signal will diminish in Db by length of run, and amount of connections with a Db loss for each. Some of the other members could elaborate on the loss for each, and often is printed right on the splitter. A DC-passing connection may be required. What is this feed coming from?
Mark Heller
"Well - I oughta....." -Jackie Gleason
#67492 - 07/07/06 11:21 AM Re: Digital CATV
wageoghe Offline
Registered: 02/14/02
Posts: 22
Loc: Huntsville, AL
You can also get excellent CATV information over at the dslreports forum:
#67493 - 07/07/06 03:00 PM Re: Digital CATV
LK Offline
Registered: 01/21/03
Posts: 1429
Loc: New Jersey
"A DC-passing connection may be required."

Yes length of cable is critical, with digital switches.

If the receiver is digital, are you sure you don't need a digital switch, rather then a splitter?

Is this a cable feed. or feed from a dish?
#67494 - 07/07/06 07:18 PM Re: Digital CATV
hbiss Offline
Registered: 12/16/03
Posts: 886
Loc: Hawthorne, NY USA
Lots of misinformation here. Digital cable is actually much more forgiving than analog. Analog will gradually degrade to noise and snow as the signal level drops. A digital signal can go much lower and the picture quality will be unaffected- until it reaches a certain point and then you get nothing.

So all of you guys who think you have to do special things for "digital" it just ain't true. Even those 2 Ghz "digital" gold plated splitters are only designed to make your wallet lighter. They are brought to you by the same folks who sell gold plated receptacles that will make your stereo sound better. Not going to happen any more than a "digital" splitter is going to make your picture better. The $2 1 Ghz ones have the same thru loss and will work just the same considering no cable system goes above 750 Mhz.

That said, doing stuff like this by the seat of your pants is not the way to go and invites problems. There is a lot more to it than running some cable and throwing splitters in somewhere to connect everything together. If you don't know how to determine and calculate signal levels and don't have the equipment to do it, well, you shouldn't be doing it.

The first place to look here would be the splitter. Bad port? Yup it happens. Try switching the home runs around and make sure the feed is on the "in". Of course the possibility exists that you may have reached that "digital point of no return" where, because of bad design and endless splitters the level to that set is below what will work.

An amplifier is not the answer until the mess is cleaned up first and then through calculation and measurement it's determined that a certain amount of gain is necessary.


[This message has been edited by hbiss (edited 07-08-2006).]

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