ZL4RFM Scroggs Hill

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in Configuration and Operation

Hi

New here so hope this is in the right place . I dont think this site is working correctly I was Listening to it on 8867 as well as ZL1ROT feed on 8867 I could hear nothing on the ZL4RFM but on the ZL1ROT loud and clear The plane I was listening to was closer to the Mosgiel site then the Rotovagus site . Not sure how to contact the owner But maybe an issue . I dont know

Tim

Comments

  • HB9TMCHB9TMC

    He does seem to have typical VDSL noise with the uplink band from 8.5 to 12 MHz and S9 noise on that frequency 8867 kHz.

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    But he doesn't seem to have left any contact information.

  • G8JNJG8JNJ

    If the antenna details given on http://zl4md.proxy.kiwisdr.com:8073/ are correct, they are using a Mini-whip antenna.

    These, like most unbalanced antennas, are prone to picking up local interference, which is a pity as they seem to have a reasonable amount of land to play with, where they could locate a better antenna.

    The Twente websdr "got lucky" with their Mini-Whip installation, but not without a fair amount of work.

    Unfortunately, this encouraged others to use the same, thinking they will obtain a similar performance, but without taking care of the location and installation parameters, they won't.

    I had a Kiwi at Goonhilly Earth Station in the UK for several years, running on what was a temporary antenna at the time, an active whip, which was plagued with local interference. The plan was to replace this with something better, but then the Covid lockdowns kicked in, and it never happened.

    I've currently got the kit back at my home, as it needs upgrading. But hopefully at some point it will get returned to the site, but with an active dipole antenna.

    Regards,

    Martin

  • G8JNJG8JNJ

    Looking at their spectrum display, it's the downstream DSL, that is problematic, which is odd at this level of amplitude.

    I wonder if they have their modem, line filters and POTS wiring setup correctly.

    Regards,

    Martin

  • HB9TMCHB9TMC

    8.5 to 12 MHz is normally the upstream (US2), from the modem to the cabinet.

    Visible is also US1, 3.75 to 5.2 MHz

    With the extent of interference, there is certainly something not good with the line. Probably a bridge tap or perhaps a broken conductor (VDSL often still works in such cases...).

  • G8JNJG8JNJ

    Yes, you are correct, it is Upstream, which makes more sense, and may be easier to fix.

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