Connect with us

shielded cat 5e

Discussion in 'Hobby Electronics' started by Heywood Jablome, Nov 29, 2004.

Scroll to continue with content
  1. Hey all,

    I have been looking everywhere for pink shielded cat 5 cable - either
    stranded or solid core, around 25 metres.

    All of the computer stores I have tried don't stock it. Middendorp
    electrical stocks it but only in a 305m reel. Same as Hills. Anyone know a
    supplier that sells by the metre or in low increments?

    I really don't want a 305m reel. Its expensive stuff because it's shielded.

    -H
     
  2. Allan

    Allan Guest

    Why do you want Shielded Cat 5 Cable?
    Do you not understand that Cat5 cable is a twisted Pair design, and does not
    require shielding, and that shielding it would make no difference.
    Iam curious what application you would need to have shielded Cat 5 cable,
    Esp. over 25 Meters
    Allan
     
  3. Hey Mr Expert, how about you try a little experiment before questioning the
    OP's sanity?

    Get a portable radio, switch to the AM band, tune off the station and hold
    it near an active CAT5 UTP cable. Hear that noise? Now switch to FM and do
    the same. Hear the noise? Got a Spectrum Analyser? Hold the probe near a
    CAT5 cable and have a look at the crap that comes out. Now, is that cable
    well shielded (NOT) and would shielding make a difference (YOU BET)?

    In an electronics development environment, particularly RF-related, the crap
    radiated by UTP cables can really screw things up.

    I'm interested in the answer to the OP's question, and also whether/where
    pre-made shielded patch cables are sold.

    D.
     


  4. I'm not after pre made patch cables. Just the cable itself. The application
    is for a home automation lighting system. The shielded cable is used to
    daisy chain all switches in the house. It is a Dynalite system that requires
    shielded Cat5 cable. I am guessing that this is because it will be in close
    proximity to 240V cable.

    Anyway, I recall a company with the word cable in it like "the cable guys"
    or "cable world" or something that stocked it by the metre. Anyone know a
    source?

    Cheers -H
     
  5. Russ

    Russ Guest

    How does Dynalite compare to C-Bus?
     
  6. Try Wiltronics - http://www.wiltronics.com.au/catalogue/shop.php?cid=71
     
  7. C-Bus is easier to sell. Nice range of flashy buttons, and is easier to
    program but Dynalite is more versatile in what you can do with each switch-
    Most of the Dynalite range is used in industrial lighting control such as
    bridges and monuments around the world, but they do have a small range for
    home automation use. In terms of cost, they are much the same.
     
  8. Phil Allison

    Phil Allison Guest

    "Heywood Jablome"

    ** How IS that lunatic John Gunton going these days ???




    .............. Phil
     
  9. Allan

    Allan Guest

    Hey Thanks for the Info,
    So what's the difference b/t the shielded and non shielded cable with how
    far away from the Cat 5 cable does the AM radio stop picking up the EMF
    noise?
    I'am not tiring to be a smart arse, I was just tiring to find out if he knew
    why he needed the shielded cable, and if it would really make any difference
    , which I see is still not answered here...
     
  10. Have you looked at the number of twists-per-inch of Cat-5e?
    Adjacent half-twists radiate the same hash with opposite
    phase, so you'll detect EMI more or less depending on whether
    your detecter is "listening" to one half-twist or more at the
    frequency of interest. When you get further away than the
    length of N twists, or when you consider a frequency whose
    wavelength is N twists or more, you'll pick up s.t. like 1/N^2
    of the hash. Or 1/N^3, I forget. Either way, that's one reason
    why Cat-6 has a higher bandwidth rating, more twists/foot.
     
  11. Do you know him?
     
  12. Phil Allison

    Phil Allison Guest

    "Heywood Jablome"

    ** Not in the biblical sense ;-0

    Met up with him when he ran Ceitex back in the late 1970s - they carried
    out the assembly ( badly ) of some audio mixers I had designed for a disco
    hire business called Jai Sound.

    Had some minor dealings with Dynalite - one of the staff there is a friend
    of mine.





    ................. Phil
     
  13. Allan

    Allan Guest

    So does the shielding stop anymore EMI getting out?
     
  14. Newsy

    Newsy Guest

    H

    I want some as well for a Dynalite installation.
    I'm happy to take a box full.
    Where are you?
    How much do you need?

    Rod
     
  15. Of course. It's not impregnable though - even the
    shielding has a finite resistivity and inductance
    which would allow some leakage. But the emisions
    would be much less, especially at very high
    frequencies (5GHz and up), where the wavelength
    is short enough that those cancelling half-twists
    don't cut it any more.
     
  16. Allan

    Allan Guest

    Cool, Thanks Clifford,
     
  17. I need about 25m. I'm in Melbourne. Where are you?
     
  18. Newsy

    Newsy Guest

    Adelaide, but that doesn't matter if you are willing to pay the postage.
    Email me on rlg000ATNOSPAMyahoo.com
    Take out the obvious.

    Rod
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-