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From: "james moritz" <j.r.moritz@herts.ac.uk>
To: <rsgb_lf_group@blacksheep.org>
Date: Thu, 20 Apr 2006 17:29:15 +0100
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Subject: RE: LF: Top load coil at ground level?
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Dear Peter, LF Group,

>>From G3PLX:


...Now I remove the two terminals of the coil and in it's place at the =
top
of the antenna I connect one end of a length of coax, with the outer =
braid
to the top of the antenna and the inner to the top hat. I run this coax =
down

the antenna. Maybe I thread it down INSIDE the antenna so that Jim =
doesn't=20
know it's there!  At the bottom of the coax I connect my loading coil...


This is fine, and the same as Dick's Topload3 diagram, but with the =
parallel
wire stub replaced by coax - but in Figure 2b of the original article, =
the
connections are different. In this case, if the open wires are replaced =
by a
coax stub, the top hat would also connected to the coax braid as well as =
the
top of the mast, and the coax inner at the top of the mast wouldn't be
connected to anything! In the description above, both terminals of the =
top
end of the transmission line are connected to something, but in Figure =
2b,
one terminal isn't connected at all.

Cheers, Jim Moritz
73 de M0BMU