Mal,
JA5FP said that the length of two electrodes earth antenna were 30m
for 3.5MHz, 60m for 1.9MHz. These length were selected by 0.8 of photo
speed for the earth.
There may be an outer circle (both send/receive capable) including of
Beverage antenna (receive capable).
These phenomena may be effect on classic antenna theory.
Try to transmit LF/VLF using the two electrodes earth antenna then
discuss on whether can or can not. We may get a new antenna theory in
our hands.
7L1RLL Rick
On Tue, 2010-08-17 at 10:35 +0100, mal hamilton wrote:
> Rick
> On 3.5 Mcs the wires were probably a 1/4 wave each, on top of the ground
> and this is totally different to short wires being used on 137 Khz or 9Kcs
> where the wires are very short in relation to wavelength.
> The configuration would need to be explained in more detail.
> de mal/g3kev
>
> ----- Original Message -----
> From: "Rick Wakatori" <[email protected]>
> To: <[email protected]>
> Sent: Tuesday, August 17, 2010 10:10 AM
> Subject: Re: LF: Earth electrodes antenna tests[Contest results]
>
>
> > Hi Mal,
> > This results was not same district or near field, but 31 districts as
> > shown multiplier factors.
> > There are about 70 districts in Japan. He worked about a half of total
> > Japan districs at 3.5MHz band. The total distance from Hokkaido Island
> > (near Sahhalin) to Okinawa islands (near Taiwan) is about 3000km long.
> > Kanto plane area (area 1) including Tokyo Metropolitan has only 8
> > disticts (8 multipliers).
> > This is an example of sending by the two earth electrodes antenna.
> > I hope more experimeters will got a same trend.
> > 7L1RLL Rick
> >
> > On Tue, 2010-08-17 at 09:27 +0100, mal hamilton wrote:
> > > This result is misleading because Japan is so densely populated with
> radio
> > > amateurs that these stations worked were probably in the Near Field. ie
> in
> > > the same district.
> > > When I was in Singapore 9V1OY although not in the near field for Japan
> the
> > > bands were buzzing all the time with Japanese acty, sounding like bees
> on a
> > > water lilly. It was virtually impossible to work other stations because
> of
> > > the endless racket.
> > > g3kev
> > >
> > > ----- Original Message -----
> > > From: "Rick Wakatori" <[email protected]>
> > > To: <[email protected]>
> > > Sent: Tuesday, August 17, 2010 7:12 AM
> > > Subject: Re: LF: Earth electrodes antenna tests[Contest results]
> > >
> > >
> > > > 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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