From Dave G3YMC
G3KEV suggests that loops are very inferior to verticals on 136. He may be
right, but experience here is not as pessimistic as he would suggest.
I use a loop as a means of getting a signal out on 136 from a QTH which many
would view as hopeless. As well as being small, the ground is mainly sand
and has a very high loss resistance. Experience of verticals on 160 and 80
has been most disappointing because of this, and although I have not yet
tried a vertical here I would expect it to be similarly disappointing.
The loop certainly offers the means to get a signal out on the band from a
small plot, and offers an antenna largely independent of ground effects - it
is also relatively unaffected by rain and other elements unlike verticals
and Marconis. Yes with the power I currently run it is by no means a DX
antenna (and I suspect as Mal says that the low angle radiation pickup is
minimal) but it allows me to have QSOs over a very satisfactory distance. I
can also receive a fair modicum of DX - OE5ODL, HB9ASB (579), OK1FIG, and
have had an excellent listener report from F6CNI.
The only station I know who uses both a loop and vertical regularly is Steve
GW4ALG. Steve admittedly runs more power than me, but has worked quite a
lot of Eu DX on his loop. Signals from him here are certainly stronger on
his vertical, but by no more than a couple of S points, and that can hardly
be classed as an enormous difference.
It is also a little unfair to say that stations with poorer set ups rely on
the station at the other end to 'make up' by having a better set up. I have
worked quite a few stations in a similar situation than myself, in
particular Des M0AYF. Des's garden is not that much bigger than mine, and
he was running less power than me (30W) into a small vertical - there was no
big station effect in my QSO with Des.
The type of loop used by Andre at the beacon however, where the return path
is via the ground conections, is likely to be lossy if treated as a loop and
hence probably cannot be directly compared. But even that has been heard
over 400 miles!
We need to put loops into perspective therefore - OK they are never going to
be band leaders, but they have offered stations like me, who for various
reasons cannot put up large antennas, at least to get on the band and share
in the activity. They deserve rather more attention than Mal is suggesting.
73s Dave G3YMC
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http://ourworld.compuserve.com/homepages/sergeantd
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