How well do Leviton's S-Video over cat5 ports work?

[miamicanes]

Today at Home Depot, I noticed that the Leviton ports that allow you to connect 2 cat5 pairs to the back of a S-video interface only cost about $9 each. Ditto, for a pair of RCA jacks for line-level stereo audio.

How well do they actually work? Are they baluns? The cheapest s-video-via-cat5 baluns I remember seeing were about $80/each. On the other hand, the $80 ones I remember seeing used a single cat5 cable to transmit s-video AND stereo audio, whereas it appears that Leviton's require one cat5 cable for the video, and one cat5 cable for the audio.

If I wanted to feed the s-video output of a DirecTV HD-DVR into one of the Leviton ports (say, 6-12' of decent-without-being-neurotic cable), routed it to the other end via ~10 feet of cat5, and connected the other end to a TV via a 12' s-video cable, would I be likely to get good video quality? Would I need a s-video amplifier?

Also on the topic of those Leviton ports... besides having plastic inserts of the wrong color, if I wanted to use one that was intended for composite video to carry the 'Y' component video signal, and use a pair intended for stereo audio to carry the Pr and Pb signals, would it be likely to work well... say, if there were a set of 6' cables at the receiver end, ~10 feet of cat5 inside the wall running up to the next floor above, and a final 15-25 foot run of cable to the TV?

Assuming they DO work, do they need shielded cat5 cable? Would using shielded cat5 cable be likely to make a meaningful difference, considering that we're talking about 10 feet of cat5e between the two jacks?

Assuming they're worth considering as a component-video option, would the RCA-jack variant ALSO be good enough to carry coaxial SPDIF (same topology... ~6' cable at receiver end, ~10' of cat5 in the wall, ~15-25' cable to the TV itself).

 

[bfisher]

I have a little experience with these - I tried using this for running to a TV about 40' away. Didn't work well at all, I had a ghosting problem. Ripped it out, bought a 50' SVideo cable and it was much better. (I don't use that anymore either - converted video system to Sage)

 

[gatchel]

I have a setup with 20' of cable from source to a second TV. Acceptable quality for a shot distance.

The HD ones are not baluns. They simply break out the signals to the CAT5 pairs. S-Video has a 40 or 50 foot limit so your mileage may vary.

The cost is so cheap that you can try it first. If it doesn't work well, your CAT5e runs are already in place for the baluns.

HD takes returns on anything...

 

[miamicanes]

In your opinion, is the quality you get using the Leviton jacks and 20' of cable appreciably worse than what you'd probably get with proper baluns, RapidRun, or a 25' s-video cable with a ~6' s-video cable on each side (simulating the cable from the source to the wall, the in-wall cat5e, and the cable from the wall to the TV)?

Even though it would obviously require a new line of faceplates and/or flying leads, I wish RapidRun had at least one that could kludge their digital/DVI-compatible "Red" cable into S-video + stereo, or at least composite video + mono, for people like me who will absolutely have a HDTV w/hdmi at the other end someday... but not for at least 2 or 3 more years, and would love to be able to at least limp w/analog video over the same in-wall cable for a couple of years in the meantime. My biggest problem right now (besides finding someone to drill a few holes for me between the suspended concrete slab (corrugated steel pan deck) between the first and second floors) is space... there's only ~3/4" between the concrete and drywall in most of the house's new walls, so unless I want to literally rip out a drywall panel and have the cables running two-deep across a foot-wide swath, I have to be a little more selective about the cables I actually pull & can't just indiscriminately pull a dozen extra cat5e for good measure ;-)

 

[gatchel]

Ouch! I see the dilemma now.

I haven't compared the difference between the CAT5e jacks and the same lenght of S Video Cable. The video is acceptable by my stantards for 4:3 video. I haven't used the baluns at all...yet. I have seen them in operation at our local Ikea where they are using Muxlab Baluns. The video looked OK but a little but fuzzy. That could have been the source, though. Hard to tell.

You could get come CAT5e and the leviton ends and move the TV's to the approximate distance in the same room and compare the signals with out drilling holes. Just a thought.

 

[ctwilliams]

I am using their keystone jacks for composite, svideo, and audio in several places. I thought the quality was fine with all of them for what I was doing, just using them for some TV's I do not watch much (guest room, etc)....

CT

 

[Sacedog]

I used the composite jacks for a 50' cable out to the backyard to run a projector for the kids birthday party. I was actually pretty impressed with the quality for standard def. One thing to keep in mind, and is very important when you are not using active baluns, make sure your cable is low skew, such as Belden's nanoskew. If you are using a high skew cable, you can get a lot of ghosting.

It's pricer than standard Cat5, but you will see the difference:

http://www.markertek.com/SearchProduct.asp...amp;pagesize=20

Note: Because of the low skew on this cable, it is not intended for data transmission.

 

[gatchel]

Isn't skew only an issue for component video? I'm curious. I think I read it somewhere.

 

[miamicanes]

Is there any official (or de-facto) relationship between skew and shielding? Or does cat5 cable come in at least 8 permutations (shielded vs unshielded, stranded vs solid, high-skew vs low-skew = 2 x 2 x 2 = 8)?

 

[Sacedog]

Isn't skew only an issue for component video? I'm curious. I think I read it somewhere.

It depends on how the cable is used. Anytime more than one pair is needed, there will be skew differences between the pairs. The Leviton RCA-110 jacks use two pairs, so they could experience issues if there is a big skew difference between the two pairs. If you are not using low skew cable with this product, you should use the two pairs that have the closest skew; either brown and orange, or blue and green. (These two pairs have the closest skew on the Belden cable that I am looking at....your cable might be different.)

As far as I know, there is no relationship between skew and physical shielding. Skew does directly affect how much interference can occur on the wire, hence, Cat 5 is a higher skew and twist rate than Cat3. The twist rate reduces interference from outside sources. The skew rate reduces interference between pairs within the cable.

 

[gatchel]

Isn't skew only an issue for component video? I'm curious. I think I read it somewhere.

The twist rate reduces interference from outside sources. The skew rate reduces interference between pairs within the cable.

Ahhh. That makes sense. I knew about the twist rate but the I didn't realize that there is the possibility for intra pair interference within the same cable. I initially thought skew was only an issue when sending component video due to the minute timing differences the red, blue, and green signals take to get from point to point.

Thanks for clairifying.

Bob

 

[miamicanes]

So if more twists = higher skew, and cat5e has by definition(?) more twists per foot than cat3... cat3 is likely to do a better job of carrying video between Leviton jacks than cat5, and especially cat5e and cat6?