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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