VDSL- Why isn't it noched?

Discussion in 'Investigations New Technology' started by Paul M0XDX, Apr 25, 2015.

  1. Paul M0XDX

    Paul M0XDX New Member

    Having just found out that my recent high noise levels on 14MHz and 7MHZ are caused by VDSL emissions (probably from a neighbour), I was wondering why VDSL isn't notched in the amateur bands in this country?
    I Googled VDSL notching in the amateur bands and several documents seem to recommend this.
    Does anybody know why this isn't being implemnted by BT/Openreach here?

    Paul, M0XDX, Mablethorpe
  2. Paul M0XDX

    Paul M0XDX New Member

    This is from a DSL forum Technical report from 2003, "TR-057":

    ...2.6 HAM Band Notching
    The VDSL spectrum covers a number of HAM radio bands. To avoid
    interference it is necessary to introduce power control (notching) in one or more
    of these bands. Following parameters are configured to support HAM band
    notching per VDSL line.
    2.6.1 HAM Band Template
    The HAM Band Template configures the HAM bands that should be notched.
    Following standard HAM bands are defined in the VDSL spectrum:
    Start Frequency
    Stop Frequency
    1810 kHz
    2000 kHz
    3500 kHz
    3800 kHz (ETSI); 4000 kHz (ANSI)
    7000 kHz
    7100 kHz (ETSI); 7300 kHz (ANSI)
    10100 kHz
    10150 kHz
    Notching for each standard band above can be enabled or disabled.
    In addition, at least two more custom notches may be specified:
    • Custom Notch 1:
    • Start Frequency in Hz in 10 Hz steps.
    • Stop Frequency in Hz in 10 Hz steps.
    • Enabled/Disabled
  3. Ken G3SDW

    Ken G3SDW Moderator

    Paul get in touch with John Rogers M0JAV m0jav@lowgables.co.uk and he can advise you what can be done and it can be.

    73

    Ken
    G3SDW
  4. Paul M0XDX

    Paul M0XDX New Member

    Hi Ken,
    I had a long and informative talk with John last night on the phone.
    I had sent him some SDR plots of the transition frequencies and he confirmed that it is VDSL noise.
    He has given me a few ideas and a couple of things to try before proceeding further.
    He also gave me some info on the notching issues.

    73
    Paul, M0XDX 5.245MHz transition.jpg
  5. Ken G3SDW

    Ken G3SDW Moderator

    Great, yes he`s the man in the know and between the two of you it will get sorted.
    Thanks for the update
    73
    Ken
    G3SDW
  6. Robin

    Robin New Member

    Hello Paul
    John will have given you all the necessary information, but could you post a brief summary of your observations at your QTH. We are trying to get members to post their experience of VDSL interference on this forum so that other members know what to look out for. How do your observations compare to my original "VDSL Emission Investigation" post?
    Thanks.
    73
    Robin G3JWI
  7. Paul M0XDX

    Paul M0XDX New Member

    Hello Robin,
    Sorry for the delayed reply, I have now posted some details on the VDSL emission forum page.
    73 Paul M0XDX
  8. Robin

    Robin New Member

    Thanks Paul. Just the sort of information we are looking for.
    73
    Robin G3JWI

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