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Re: [loopantennas] how deep are the loop minima

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  • fernando talamantes
    Hi Vojtech: you must try at more distance from power lines. if u are living very close, you cant get a good null because the antenna is receiving noise
    Message 1 of 4 , Feb 10, 2013
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      Hi Vojtech: you must try at more distance from power lines. if u are living very close, you cant get a good null because the antenna is receiving noise transmited along the power line. the transmiter (power line) is not a puntual antenna and probably are receiving noise from angles different than the minimal rx .
      73
      Fernando XE2EJ

      --- On Sun, 2/10/13, Vojtech <bubnikv@...> wrote:

      From: Vojtech <bubnikv@...>
      Subject: [loopantennas] how deep are the loop minima
      To: loopantennas@yahoogroups.com
      Date: Sunday, February 10, 2013, 9:09 AM

       
      Hello.

      I measured the maximum and minimum band noise of my 1ft dmr loop standing on a window sill. I am living near a HV power line and the attenuation of the powerline noise when turned towards the noise source is in the ballpark of -10dB (-13dB if I am optimistic). Is this a usual value, or shall I strive to do better?

      Thanks, Vojtech OK1IAK

    • vbifyz
      You can also try and tilt the loop around the horizontal axis. This may give you few more dB. This is my actual observation. Note that the orientation that
      Message 2 of 4 , Feb 11, 2013
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        You can also try and tilt the loop around the horizontal axis. This may give you few more dB. This is my actual observation.
        Note that the orientation that gives maximum signal-to-noise is not necessary the same as the lowest noise, but it is usually pretty close.

        73, Mike

        --- In loopantennas@yahoogroups.com, fernando talamantes wrote:
        >
        > Hi Vojtech: you must try at more distance from power lines. if u are living very close, you cant get a good null because the antenna is receiving noise transmited along the power line. the transmiter (power line) is not a puntual antenna and probably are receiving noise from angles different than the minimal rx .
        > 73
        > Fernando XE2EJ
        >
        > --- On Sun, 2/10/13, Vojtech wrote:
        >
        >
        > From: Vojtech
        > Subject: [loopantennas] how deep are the loop minima
        > To: loopantennas@yahoogroups.com
        > Date: Sunday, February 10, 2013, 9:09 AM
        >
        >
        >
        >  
        >
        >
        >
        > Hello.
        >
        > I measured the maximum and minimum band noise of my 1ft dmr loop standing on a window sill. I am living near a HV power line and the attenuation of the powerline noise when turned towards the noise source is in the ballpark of -10dB (-13dB if I am optimistic). Is this a usual value, or shall I strive to do better?
        >
        > Thanks, Vojtech OK1IAK
        >
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