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Hello Niels, LF group,
Yes, it is a rather large loop! I have a few
pix of it if anyone would like to
see how I've built it. Your guess of the
inductance is close, I measured
it with my LCR-55 meter and it's 2150 uH. or about
2.1 mH. According
to Reg's loop program the self resonance is about
800 kHz. and the Q
is 383, but I've no way to verify the
latter.
At this point I'm game to try any suggestions to
see if I can improve on
the performance (or lack thereof at the
moment) I think I'll try a simple
one turn unshielded pickup loop next, but I'll
certainly keep your idea
of a capacitive divider in mind.
73, J.B. Weazle McCreath, VE3EAR -
VE3WZL
Dr om!
Quite a big loop you have made
there!
I would not recommend the use of a pickup loop
at all. It is rather
difficult to predict the degree of coupling
between the loop prober and
the pickup loop.
From your description I guess that your
loop inductance is about 2 mH,
as for the Q of the loop I would say it
lies between 20 and 50.
Why not try to scrap the heavy RG213 loop and
instead use a
capacitive divider . If you try a capacitor of
10 to 22 nF in series
with your variable capacitor, you might have
success.
As for the question of balancing etc. in order
to avoid capacitive signal
pickup, I suggest you try to solve that problem
with an isolating
transformer. But let that be a second
exercise!
73
Niels/OZ8NJ+
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