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AVMASTER
03-26-2004, 01:48 PM
one of my distributors told me that if i go over 40' with copper based DVI i would need to use fiber optic based DVI to eliminate signal lose. has anyone ever used this? any truth to signal lose at certain lenght?

uncooked
03-26-2004, 07:03 PM
yea you lose a bit, but not an incredible amount, 40 ft isnt very far so you would barely lose any signal.

if you think about cable coax do you know how many hundreds or thousands of feet that runs before it gets to your house, and cable video is usually "ok" good, and the sound is ok for stereo.

so 40 ft is nothing!

cam
03-26-2004, 07:35 PM
one of my distributors told me that if i go over 40' with copper based DVI i would need to use fiber optic based DVI to eliminate signal lose. has anyone ever used this? any truth to signal lose at certain lenght?
Your biggest concerns should be if you are getting any unwanted interference from other cables such as power, video, or audio cables. Cable length should not be a problem in your house. Cable managment could be.

mtrycraft
03-26-2004, 10:26 PM
one of my distributors told me that if i go over 40' with copper based DVI i would need to use fiber optic based DVI to eliminate signal lose. has anyone ever used this? any truth to signal lose at certain lenght?


Can you do a visual test with such a long cable on the cheap?

DVI is not 75 ohms as far as I know. Widescreen Review had a video cable test many years ago. In that the tester indicated that a 1dB signal loss is needed to notice a visible difference.

Maybe you can find out the DVI specs for signal loss at 25 ft, 100 ft?

woodman
03-27-2004, 08:28 AM
Your distributor is a classic case of "The Peter Principle" in action ... someone who's moved up into a job where he is not competent to fulfill the role. He quite simply does not know just whatinthehell he's talking about.

The plain, unvarnished truth of the matter is, that digital signals are far more robust and less susceptible to meaningful signal losses than analog signals are ... that's one of the "benefits" of digital technologies as opposed to analog ones. Since you can send an analog video signal at least 75'-100' of copper-based coax before a noticeable degradation of signal quality is likely to be perceived, I'd estimate that you could probably send a DVI signal through at least double that distance without a problem.

One has to wonder whether maybe - just maybe, he happens to have some 100' lengths of Toslink cable that he's desperately trying to "find a home for" doesn't it? Either that or, he's a totally incompetent boob that's trying to feign competence in a field in which his technical expertise is sorely lacking!.

AVMASTER
03-27-2004, 01:04 PM
i've run DVI cables up to 30' without a problem and i'm sure longer would be no problem but what really peeked my inquiry was that there's a fiber optic DVI cable (18 years in this business and still so much more to explore). I should have asked if theres' any benefit in using it. Thanks to all

woodman
03-27-2004, 01:45 PM
i've run DVI cables up to 30' without a problem and i'm sure longer would be no problem but what really peeked my inquiry was that there's a fiber optic DVI cable (18 years in this business and still so much more to explore). I should have asked if theres' any benefit in using it. Thanks to all

NO there isn't.

mtrycraft
03-27-2004, 09:41 PM
i've run DVI cables up to 30' without a problem and i'm sure longer would be no problem but what really peeked my inquiry was that there's a fiber optic DVI cable (18 years in this business and still so much more to explore). I should have asked if theres' any benefit in using it. Thanks to all


I overlooked that it sends digital signals. Not to worry in that case as woodman stated.

The video band that it sends is nothing compared to what digital signals are being sent much further without a problem.