Hi Tony, It probably depends how far away the detector was you need to be
about 1km out for certain results.
Alan
----- Original Message -----
From: "Tony" <[email protected]>
To: <[email protected]>
Sent: Monday, August 16, 2010 5:20 PM
Subject: Re: LF: Re: Earth electrode antenna tests
> Hi Alan.
>
> Last week I hooked up my sig genny to the loop and the maximum signal
> was at right angles to the wire, so I was expecting receive to be the
same.
> Seems not.
>
> Tony, EI8JK
>
>
> On 16/08/2010 16:51, Alan Melia wrote:
> > Hi Tony, why do you think the directivity is wrong? It looks as though
they
> > are operating like loops with the majority of the loop area in the
ground.
> > This is a fairly common appreciation of ground "aerials" though Dave
Gibson
> > doesnt seem to agree
> > :-))
> >
> > Alan
> > G3NYK
> >
> > ----- Original Message -----
> > From: "Tony"<[email protected]>
> > To:<[email protected]>
> > Sent: Monday, August 16, 2010 3:35 PM
> > Subject: LF: Earth electrode antenna tests
> >
> >
> >> Yesterday I spent some time playing with different antennae.
> >> I started by laying out another wire 52m long orientated roughly
> >> north/south and then I shortened my original wire also to be 52m and
> >> this one is east/west, both terminated with an earth rod.
> >> Results were not as expected however as although the two earth
electrode
> >> antennae show most definite directivity they were the wrong direction.
> >>
> >> I monitored BBC R. Bristol on 1548 KHz which is about 500 Km due east
of
> >> me and on the inverted L (tuned VSWR 1.6:1) I could just detect a
> >> carrier heterodyne, on the N/S earth electrode antenna it was S1 but on
> >> the E/W earth electrode antenna it was S3.
> >> RNE5 on 531 KHz about 960 Km due south of me was S3 on the E/W and S8
on
> >> the N/S
> >>
> >> HGA22 (135 KHz) to my east was S4 on the E/W and S1 on N/S
> >>
> >> Readings were taken about 12:00 utc so most definitely ground wave.
> >>
> >> I was expecting the directivity to be broadside on the earth electrode
> >> antennae, but they seem to behave like a Beverage in that respect, but
> >> something that I think I will investigate further, maybe see if there
is
> >> any difference if I terminate them with a resistor.
> >> I'm sure Mal is correct though that they would be useless to TX through
> >> but for RX they seem to have possibilities especially after dark as
they
> >> are a lot quieter.
> >>
> >> All good fun.
> >> 73, Tony, EI8JK.
> >>
> >
> >
> >
>
>
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