John, W1TAG said:
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It is occasionally useful to suggest to the newer readers of this reflector
that despite the advice given by G3KEV, significant fun and useful
knowledge may be had by LF experimenters who have neither a large wallet or
a large
amount of real estate.
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Yes that is true. I5TGC's antenna system is probably the best example of
what can be done from a small QTH closely followed by the arrangement at
G3XDV.
Mal G3KEV said:
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Lots of real estate is not necessary for a 100 ft vertical antenna, about
6ft x 6ft concrete base but the average telescopic tower base is about 1 sq
ft. and does not require guys for wire antennas. One insulated radial
running around the garden enclosure will work well. against a base loaded
or
gamma matched mast...............
.............If you are happy with you crystal set why change.
Any radio amateur serious about LF activities needs a farm or ranch of some
sort!!!!!!!!
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A bit of contadiction there.
A 100ft (33m) telescopic tower is not a sensible option for a small garden
for obvious reasons. Commercial towers for LF, were the tower itself is the
antenna element have to be insulated from ground at the base. For a
self-supporting structure this means a tower structure similar to that used
by Decca. Otherwise it means guying. Gamma or Omega matching systems can be
used at 160m but are definitely not on at LF. How long would your matching
rod have to be do you think?
You need a lot of wire for a resonant insulated radial at 136kHz.
My suburban LF antenna has been described as a 'bit of wet string' by Mal
but it does seem to work OK.
Regards,
Peter, G3LDO
e-mail <[email protected]>
Web <http://web.ukonline.co.uk/g3ldo>
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