Hi Tony and the others,
Talking with JA5FP, Contest results using the two electrodes earth
antenna were as follows:
(1)JARL Field Day Contest: 3.5MHz, 86 QSOs, 31 multi.
(2)KCJ Contest: 1.9MHz, 12 QSOs, 8 multi.
Both were 50W output.
Where multiply factor in these contests were number of prefectures
workedin Japan, but not DX station.
7L1RLL Rick
On Tue, 2010-08-17 at 12:01 +0900, Rick Wakatori wrote:
> Hi Tony,
> In addition to my previous introduction I forgot to say a moint :
> (3)There is a length dependency.
> The two electrodes earth anntena of 2 times long can be received 3 dB
> up.
> Confirm the above.
> 73
> 7L1RLL Rick
>
> On Tue, 2010-08-17 at 10:10 +0900, Rick Wakatori wrote:
> > Hi Tony,
> > Thanks for the confirmation on directivity of the two electrodes earth
> > antenna.
> > The JA5FP's group said as follows:
> > (1)Same directivity exists in a short distance.
> > (2)Dried earth is good for transmittion. Wet ground does not work as a
> > good antenna. an imaginal loop may be shortened in a half.
> >
> > Try the above phenomenons.
> > 7L1RLL Rick
> >
> > On Mon, 2010-08-16 at 15:35 +0100, Tony wrote:
> > > 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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