On Apr 27, 9:22*am, Bill M wrote:
Bill Janssen wrote:
How about making an Air Core Toroid. That can be made using a wax core.
Then after winding it,
some QDope or something in strips to hold the windings and then melting
the wax. Or maybe a foam
plastic core.

Bill K7NOM

There was a manufacturer in the 20s that used a coil like that. *Thorola
- they called them donut coils. *Looks like they just wound them on a
small form, maybe 1 inch, and then slid it off and bent it around
afterwards into the form of a donut.

Never heard any comment yeah or nay about their efficacy.

-Bill M

I think the best one I ever made used an oatmeal box for a form. Big
air core coils seems to be the way to go. I built a kit that used a
pair of loopstick coils and the best I could ever do wiith it was a
couple of local stations. I think it was a Heathkit. A good RF ground
seemed to benifit the receiver more than the antenna. Back in the day
my father had a service station with about two acres of concrete out
front. I was able to connect into a ground point that hooked it up to
all the wire and rebar in the concrete.



Jimmie