Mike,

Ignore the old wives. The extra resistance due to soldered joints around a
copper octogon is unmeasurable. Wipe off any visible surplus solder while
hot or use fine glass-paper. I finish off with metal polish and a coating of
clear yatch laquer. A beautiful, long lasting appearance .

The usual conductor material in commercial magloops is an aluminium alloy.
Its lighter, cheaper, weather resistant and you can't tell the difference in
radio performance. By far the best way of improving magloop performance is
to increase the circumference of the main loop. Double the circumference,
half the capacitance and the difference will astound you. However there's
nothing more to be gained after the circumference has increased above about
3/8ths wavelength at the frequency of interest.

Just make the main loop diameter, capacitor value, conductor diameter and
coupling loop diameter according to program Magloop4.

Ideally, there should be no direct connection between coupling loop and main
loop. Otherwise RF currents will flow on the coax feedline and can make a
mess of the null in radiation pattern. A few ferrite sleeves over the
antenna end of the coax will help.

The coax used in the coupling loop can be junked. The Faraday thing is a
waste of time and material. Just use a length of wire stiff enough for it to
be self-supporting. It can then be easily adjusted for diameter.
Alternatively, if made a little oversize, it can easily be rotated a little
relative to the main loop to vary the coupling coefficient.

If the loop diameter is adjusted for the 80m band it will be near enough for
the 160m and 40m bands too. If you do nothing with the program except
change frequency you will see the diameter of the coupling loop changes very
little from one band to another.

But if you have some wierd, bulky, home-brew contraption for the tuning
capacitor then in practice things may behave less conveniently.

You won't need an antenna analyser. Just connect a transceiver with its
ordinary SWR meter to the antenna and it should work right away. Don't take
undue notice of the SWR meter till exceeds 1.5 : 1.

It is the transceiver with its own SWR meter which has to be kept happy -
NOT the analyser.

If you've never used a magloop before then it may take a little time to get
used to the VERY narrow bandwidth especially on 160m and 80m.

Just go ahead, finish construction and stop worrying.
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Reg, G4FGQ