S-Video over Cat5E WITHOUT baluns?

Composite < S-Video < Component

Component is better than S-Video. Component is 3 runs of RG6 while Composite is just 1 run.

You might be able to get away with 3-5' but not 40'. RG6 is still better.

The BalUn is to match the impedance of the video source to the cable, and to match the cable to the load.
Video is designed to used a coax cable, with a 75 Ohm characteristic impedance.
Cat5 is not coax, it's twisted pair, and it has a characteristic impedance of 100 Ohms...resulting in a mismatch. An impedance mismatch at high frequencies results in signal reflections, and the inherent loss of 'quality'.

Because Cat5 is used for high speed data, some people, who don't know any better, think it would be ideal for video frequencies as well....they're mistaken.

I've used the Leviton quickport S-Video over cat5 jacks with success on short runs.

Search for "leviton 40734-sv" should be able to find them for less than $10 an end.

Paul

Interesting comment. What's your reaction to the current trend of video over Cat5 by, say, Crestron and Kaleidescape?

crestrons devices are in essence expensive multi port baluns which make up for the impedence difference as stated above.

Kaleidascape does not send video over cat5. There configuration is tcp/ip (data packets) to a local player which converts the data stream into a video stream.

Usiing a high speed op-amp for unbalanced to balanced conversion is much better then the use of a transformer...but the additional cost over coax, and passing the signal through extra amplifiers, isn't worth it, unless you have no choice but to use cat5.

Cygnus111 - Back to your question, and repeating what Paul @ SBSmarthomes said, Leviton makes a S-video connector to be used with cat 5e cable. Just terminate the cable directly on the back of the insert. We've used these with success for runs of up to 100'.

http://www.levitonvoicedata.com/cata...ildpageid=3375

You should be able to find them online or at a local Graybar. Hope this helps.

Matt

We also use the Leviton 40734 with good success. FWIW, they are usually available on eBay. There's some there now.

Sorry that this has gotten a little off-topic.

What's been your experience with using component video over Cat5? If you were doing a prewire of a new home and delivering component video to 5 or more zones, would you run 3 coax to each or us Cat5?

3 coax.

Three coax cables are cheaper then a cat5 with BalUns . There is insertion loss from the baluns, or noise and distortion added from the op-amps....why would you want that?

Dumb question. Are there RCA connectors specifically for RG6?

We're doing a retrofit that involves about 6,000 feet of video cabling if we use coax and about 2,000 if we use Cat5. Not wanting to compromise video quality but also not wanting to run 6,000 feet of coax, we did some benchmarks of component video over 3 coax and over 1 Cat5 at various lengths from 50 to 250 feet and found no measurably significant difference in video quality. Nonetheless, coax has been used for so long that it's the safe bet. That's the dilemma.

You can use direct compression or crimp style RCA connectors made for Coax, or do like alot of us do, and use RCA to F-Type adatpers, like this:

http://www.radioshack.com/product/in...entPage=search

It's also what the video interface is designed to use. Notice how coaxial connectors are used for video (RCA or BNC)...as opposed to screw terminals, or an RJ45 connector.
The interface expects to 'see' a coax cable, with a 76 Ohm characteristic impedance...a twisted pair can't provide that.

Researching my current needs, I guess I am a bit confused... I'm in need of the following:

1) Composite Video (no HD) and analog L/R to a room about 75-100 ft away


I was under the impression that I could run all three signals over a single CAT5e cable, but needed a balun on each side (at about $100 each side). but then I see that Leviton has this QuickPort RCA and S-Video 110-Type - modular insert for about $5? Hence I would reduce my cost from $200 to about $10?

Correct, you should be able to run a composite video and analog audio signal over 5e that distance without any issues.

I wonder why they keep putting coaxial connectors on video inputs and outputs, instead of screw terminals, or RJ45's?

So from what I can gather, Targus is against this idea

For my situation, I need to run a video and R/L analog audio to a cabinet and it will be split to broadcast to 3 small tvs (21 inch)... I am trying to prevent having 12 RG6 cables coming into a box... it would be MUCH easier with 4 Cat5e. With baluns this would be about $800....

I did notice that Leviton sells RCA to Cat5e plugs... I got the spec sheet from them, and they advertise being for 10-40 ft composite video, audio, or s-video runs...

All in all, with 21 inch tv's how bad would any signal degradation really be? I'm more concerned about damage to my sending unit from mismatched impedence (if that is possible). Bottom line is that I could run either, just one would be a heck of alot more difficult; and if the performance degradation is minimal then it will make my decision easier.

The kind of signal degradation you get from impedance mismatches - ghosting, for example, would be very noticable on a 21" set. I would be very careful about doing this at 75-100 ft. My very rough back of the envelope says that you could see significant ghosting 5-7 pixels off on a 720p set.

Thanks Andrew- I also need to run signals from standard consumer analog audio (RCA connector-R/L) outputs from a CD player to an amp about 75 ft away. I was also hoping to do this over Cat5e. Would the audio also be affected, or is the noise much more a problem for the video?

The big problem for video is reflections. Reflections are not likely to be a problem for audio. There is some disagreement as to whether they are theoretically present - but nobody has ever been able to hear them over those kinds of distances in a controlled test.

There is some risk of noise such as AC hum but CAT5e is twisted pair and that cancels out almost all audio noise.

My bigger concern with the audio over cat5e is loss of bass response (and 60 hz hum). And if I understand correctly, Cat5e is twisted pair, but unshielded. So I even thought about just some form of shielded 4 conductor wire for the audio.

No technical reason you should lose bass response if there is no noise problem.

i was searching around online and came across the products mentiones RCA via CAt5 and S video via CAT5 as well. I am very tempted to use this because of the lack of space in the wall when I am trying to do this via a conduit, the run is only 5 feet or less from the middle of the wall there the TV is to just above the floor, where I would connect my components.. so far the word is that its ok? If I am afraid I would loose quiality I would get something that would correct the impedence for the video ? being able to punch down is great I save lots of space with having to worry about the terminals/connectors etc.

Now my only problem is making 2 HDMI cables feed through a conduit.. I know there is a company that makes a special coax so it goes from hdmi to coax within the walls.. but then do not make short lengths which i need.. and so far only thing I have found is HDMI to HDMi decora plates... which is ok if there is no other option...

let me know if you know something i do not thanks people

This is a common myth. Twisted pairs do not eliminate any noise. Differential transmitters and receivers do.

does anyone know anything about running 2 hdmi side by side, this is for in wall.. thanks