I tried to make a loop with flatcable once and was not very happy with the
result either. Maybe the rather large stray-capacitance between the
windings is decreasing the loop performance ? Replacing the flatcable by
0.7mm emailled Cu-wire (all windings spaced +/- 5mm) was working much better.
But at the end I came to the conclusion that the loop was no better than my
vertical (but also no worse), because I have little or no problems with
'electric smog' at my QTH.
But for those with rather high noiselevels and/or limited space a loop may
be the best receiving antenna.
73, Rik ON7YD
At 17:19 10/01/00 +0100, OK1FIG wrote:
Hello LowFers.
I have made loop ant for rx and it seems not to work satisfactorily. Size is
1.75m x 1.75m. Everything is done as usual, with grounded middle and
amplifier with 2 x BF245, tuned properly, etc. Output level from the
amplifier is high enough. I can hear Greek RTTY, also galloping horses a
little, but no poor HAM sigs. My LW 40m, that is in average height of about
6 m only, is much better. The only thing I am in doubt is the number of
turns. It has got only 18 turns (I used flat cable that was available at the
moment). Could this be reason for the bad results? What are your
experiencies with loop ant? Can loop ant be as good as "big" Marconi?
73! Petr, OK1FIG
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