[Lowfer] coil guts

[Peter Barick]

Hi Eric,

Ah, Loading Coils: the smell freshly wound pvc coated windings, the
nostril curl from hot solder resin, the feel of a fleshly wound form.
Great stuff to wax over. :-/

As Bill already said go with the big stuff. Sure you could use what's
on hand but it would miss the mark I'm sure you'd like to achieve. No.
14 solid is a good choice. Ideally it would not have pvc insulation and
preferably enameled, though Teflon is V good--and expensive. But, gee,
for low cost and high performance, most home stores have 500 feet spools
for $15. My guess is you'll need 300 feet for the main coil, BUT, and
depending on where it is placed (top mounted, more; bottom, less) and if
a separate tuning coil is used (variometer), it will vary.

So minimize the guessing and see this at Lyle's site:
   awg-coil.zip -- Calculates wire diameters and loading coil
properties

It's intuitive to use and great to play "what if" with on coil
dimensions. If you use it, keep in mind that a turn-to-turn dimension
parameter is called for. For using pvc electrical wire that's touching,
that's a 1 wire size gap due to the separating insulations between
conductors. Though for enameled wire, "touching" is no gap. :-)

Last tip. There have been many list posts on best/ideal L/W coil
dimensions. A basic starting point is to think 2.5*D : L, that's over
twice as fat as high. However you may be back ended into using a handy
former, e.g., a 5-gal plastic pale or two in tandem. Further, if your
calculations call for a larger D for the former and you've tagged the
rather sturdy 5-gal pale, you can "expand" it! Yeah, by, say, attaching
spacing material  axially to the pale to "Beef" it up for a larger
diameter. Dry, varnished wood, if used in an enclosure, or say Styrofoam
packaging strips for other installations.

Oh, and Last Tip + 1. Winding 100+ turns on the pale  :-{  can be a
challenge, esp, if you only have two hands--I reco 4 to keep sane. I did
it myself with two, though, by making a spinning device to hold and
allow the pale to rotate. Made it to be clamped into a big vice, had a
temp cover for the open pale end to maintain centering about its axis,
then just wound. And may you have fewer kinks than I've cursed at.

Oops, must issue this piece of advice too. So, Tip + 2: Before you
begin winding, prepare the form with beginning and ending terminals to
secure those ends. Can be simple as two adjacent wire-sized holes each
end or actual terminal lugs. You won't be sorry you did so or possibly
risk loosing those turns. :-))

GL on yer project, Eric. Hope I didn't sound tooooo pedant. Let us know
how all works out, huh.

Peter, who had part of the loading coil for the vertical rx ant. blown
off it's perch last night in mighty stiff wind gusts. Though odd, I
thought the 6-foot multi-turn loop was gunna go as it has a large
plywood center plate w/ holes in it for the 5 arms. It shook but held.