From Dave G3YMC
G3KEV wrote:
Maybe your friends are transmitting on full size loops.
Let me know how you get on and try a vertical as well for comparison.
As one of those 'friends' perhaps I should comment!
Mal will presumably expect his large 'normal' antenna to outperform a loop at
the
same location unless it is very large, as he has a very large site and can
erect big
antennas. I have a very small site, well shielded with poor ground conditions.
My
loop is a means to get on the band where I would not otherwise be able to do
so, and
to be realistic I do not expect big results from my qth whatever I do. I have
recently done comparitive tests with a 10m top loaded vertical, the best I can
sensibly achieve, and there is certainly not the huge improvement Mal suggests.
Details of these tests are on my website at
http://www.dsergeant.btinternet.co.uk/vertical.htm.
It may be that the vertical is not optimised, and in anycase is difficult to get
clear of vegetation etc - the very problem Bill Ashlock in the USA has which he
has
overcome with loops. There are some signals which I can hear better on the
vertical,
but they are few and generally in the direction of the loop nulls, and in a
typical
urban location local noise normally makes the loop the best all round antenna.
No
big expectations of dx here - if Mal can only just hear me he should remember
it is
325km and no mean distance for my set up. It may be a compromise, and
certainly does
not perform like some setups do, but the loop does at least get me on the air
from a
difficult qth.
I am currently building an Elecraft K2 10W hf transceiver. When that is
complete
shortly I shall devoting far more time to the hf bands. With normal cw
activity on
136 at an all time low I can no longer devote all my time to that.
73s Dave G3YMC
[email protected]
[email protected]
http://www.dsergeant.btinternet.co.uk
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