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LAWRENCE MAYHEAD wrote:
OK Mal,
but from the Rx point of view a strong signal is not important so long
as it is enough to overcome reciever noise surely?
Lawerence. I am not offended. I
like a good discussion as long as it is based on a sound fundation
but there is a lot of nonsense discussed on this medium. You do not always
get enough signal from small loops and low horizontal wires. A german station
published some figures the other day and where his vertical gave a signal
strength of some 30uv the loop was 0.25 uv and this was a loud commercial
station. The majority of amateur stations transmitting on 137 khz
would not have been heard by him on his loop. I have tried this on 160
metres using a 40 metre vertical quad loop resonated for 160m and compared
it to my inv L up at 100 ft.
On short/medium haul up to say
2000 miles the loop was good but beyond that for the far east, Malaysia/Australia/Japan
etc I could not even hear the signals, whereas the signals on the inv L
were perfectly readable. The loop was pointing in the correct direction.
On LF for a few hundred miles a
loop will probably give some results but when looking at say 3000 k/metres
and beyond it is doubtful and for TX useless.
When GW4ALG uses his loop I can
barely hear him. When he switches to 60ft vertical 589. When G6RO was using
a loop he was at best 559 with qsb and now he has changed to a vertical
he is 599. It speaks for itself.
73 de Mal/G3KEV
It seems to me that what is important
is sig/noise ratio and this depends not so much on the capture area
but more on the elevation angle,directivity etc. I also have experimented
over the years and am constantly amazed at what there is to be discovered,not
the least on LF where many things are different especially the effects
of ground.Anyway my remarks were not meant to be critical,they were intended
to be constructive and I hope you have not taken offence.73s Laurie.
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