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I want to use CAT5e UTP cabling to carry audio and video over distances of maybe 150 feet or so.

I plan to use the CAT5e cable as follows:

  • one wire pair for a composite video signal
  • one wire pair for the left audio channel
  • one wire pair for the right audio channel
  • one wire pair left unused for the time being

I may also use the CAT5e cable as follows:

  • one wire pair for s-video lumen channel
  • one wire pair for s-video chroma channel
  • one wire pair for the left audio channel
  • one wire pair for the right audio channel

I have had success in the tests I have performed, and believe it is because CAT5e is rated to 350 MHz, while the video signal is only a fraction of that bandwidth, and the audio channels are even narrower.

I plan to install runs of CAT5e between the source (VCR/DVD player or computer) and the display (TV or DLP projector) in dozens of rooms, and want the inheritor to be able to pick up where I left off without scratching his or her head any saying 'WTF?'.


Questions:

Are there existing standards for either of these applications, as far as which color wire pairs to use for what?

Are there any good sources for CAT5e wire-color-coded punchdown (110-style) keystones or wallplates that terminate into red/white/yellow female RCA jacks or red/white female RCA jacks and a female s-video jack?

Thanks in advance!

eleven81
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  • Are you sending a differential signal? If not (and typically this application doesn't), you may pick up interference. That's why a shielded cable is typically used for this type of installation. – Brian Knoblauch Jun 03 '09 at 14:06

3 Answers3

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The thing you're looking for are called Baluns:

For Distributing Audio/Video Via Cat5 Cable

Today's A/V industry has created the need to send high resolution audio and video signals over increasingly long distances of cable. However, the size and cost of the video cabling, especially when long lengths are involved, had created a challenge. As needs and technology change, future cable replacement can be quite costly.

A solution has been developed to tackle this problem. By placing "balun" adaptors at each end, signals can be adapted to be effectively sent over long distances of Cat5 cable.

i found a company that has a whole product page of them.

One of the product pics has this schematic on the actual device: alt text
(source: mcmelectronics.com)

So you can steal their pinouts and use that.

Glorfindel
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Ian Boyd
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    Exactly this is the answer. Using a balun is the way to adapt impedances between devices. You could use an active balun (transmitter) on the tx side, and passive baluns on the input connectors of the tvs, through a parallel circuit of the cable. – Manuel Ferreria Jun 03 '09 at 15:06
  • Actually all Ethernet network devices have baluns in them, to eliminate a voltage bias between two devices. – Brad Gilbert Jul 01 '09 at 03:57
  • They also sell Keystone jacks http://www.mcmelectronics.com/product/MCM-CUSTOM-AUDIO-50-7760-/50-7760 – Brad Gilbert Jul 01 '09 at 04:18
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I am aware that this not so much what you are looking for but you may be interested. Check out the DLNA standard. It uses networking cabling and protocols to transport video information.

Antoine Benkemoun
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  • Thanks for the idea, but I just want to use the physical CAT5e media to transport the electromagnetic signals over short distances. – eleven81 Jun 03 '09 at 13:58
  • If you're indeed looking for short distances and a cheap installation, you can use CAT5e media. Be aware that AV cabling supports lesser distances and experience worse signal then network signals. – Antoine Benkemoun Jun 03 '09 at 14:15
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Sonance is providing an adapter for their own audio/video-system, that could fit your needs.

Phil Swiss
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  • i, am i'm sure the OP, would be very interested to know the pinouts on that thing. If they're doing it, it now at least somewhat a standard :) – Ian Boyd Jun 03 '09 at 14:35