Signal Leakage through Coax Cable?

Discussion in 'General Electronics Chat' started by tronicsrookie, Sep 6, 2011.

  1. tronicsrookie

    Thread Starter New Member

    Aug 22, 2011
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    Is there a special technique that can be employed to tap into Signal Leakage through Coax Cable, used by Cable TV operators?

    What kind of antenna to be placed near a cable? and will it help to amplify before feeding into TV Tuner?
     
  2. bertus

    Administrator

    Apr 5, 2008
    15,647
    2,346
    Hello,

    If the cable is not yours, it would be illegal to tap it.
    Normaly you will hardly find any signal outside the coax.

    Bertus
     
  3. tronicsrookie

    Thread Starter New Member

    Aug 22, 2011
    14
    0
    I do pay my monthly subscription fees to my Cable Operator. This is just to experiment.

    One of my friend (Who doesn't pay his) has used this design, see in attached picture, successfully. He receives everything without any noise. I want to come up with a better design, one which doesn't require you to physically contact wire. Antenna should be at least few meters away from wire.
     
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  4. #12

    Expert

    Nov 30, 2010
    16,283
    6,795
    I refuse to answer on the grounds that it may tend to incriminate you.
     
  5. Papabravo

    Expert

    Feb 24, 2006
    10,140
    1,790
    Ethernet LAN (thick) cable often used what we called a vampire tap to pierce the outer jacket, shield, inner insulation and make contact with the center conductor. This technique is also used in plumbing to connect an automatic ice-maker in a refrigerator to an existing water line. Don't know if they exist for CATV cable.
     
  6. saturation

    Member

    Dec 21, 2008
    22
    4
    There are many ways to tap coax cable but with the switch to digital TV in the USA, nearly all you'll get are complex encrypted data streams; the same cable now carries HDTV, subchannels and Internet. Even if you stole the cable decoder box, most vendors require a sync of the internal boxes serial number, like a hardwired MAC address, against its userbase. Even if you are legitimate and have a true account, but decided to buy a box off eBay, chances of it working are fairly nil, at least in the USA. Most cable theft issues were with analog, as all it required was signal interception and finding the proper modulation.
     
  7. tronicsrookie

    Thread Starter New Member

    Aug 22, 2011
    14
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    Yes it's analog without STBs.
     
  8. saturation

    Member

    Dec 21, 2008
    22
    4
    If its legal, the best way is simply to cut the cable and put a splitter; there was a vampire tapper for CATV cable but its not sold openly except to repair industry; it doesn't provide optimal quality but convenience for troubleshooting.

    The image provided is curious if it works; cable shielding ground and prevents leakage by surrounding the inner core, so having a long shaft as pictured will unlikely pick up the signal, unless you take a cable stripper and strip off the shielding down to the inner core.

     
    Last edited: Sep 7, 2011
  9. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    4,769
    969
    yep just add a splitter. No point in coming up with a better design for an illegal practice.
    Lawyers don't care how fancy your illegal device is.. Illegal is illegal.
     
  10. tronicsrookie

    Thread Starter New Member

    Aug 22, 2011
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    Once again, this is not illegal, ofcourse I won't be on wrong side of law. I think, I got what i needed from a RF leakage mobile unit's patent diagram online.
     
  11. saturation

    Member

    Dec 21, 2008
    22
    4
    Getting cable signal from leakage from a break in the cable is possible, but the quality is YMMV. Its common for cable companies to find it during routine maintenance and repair it as its against FCC rules to allow it to continue. The signal may not strong enough to give good picture, but its almost certain enough to cause interference.

    http://www.anarc.org/wtfda/cable_leakage.htm

    http://cabletvforums.com/cable-industry-news/1455-stealing-cable.html

    For quality reasons, leakage is unreliable while splicing can guarantee it. If your application is legitimate, why bother with accidental or intentional leakage when a splice gives you the best result.
     
    Last edited: Sep 9, 2011
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