[TowerTalk] 40M rotary dipole

[john at kk9a.com]

2.4 OD mix 31 cores are significantly less money elsewhere.

John KK9A

To:	Dan Maguire via TowerTalk <towertalk at contesting.com>
Subject:	Re: [TowerTalk] 40M rotary dipole
From:	Dave Sublette <k4to at arrl.net>
Date:	Wed, 20 Sep 2017 10:31:14 -0400


Thanks for all the suggestions on the RF choke.  I read the article by
K9YC and
concluded that the best approach wold be to wind RG8X around 6 Fair-Rite
toroids made from type 31 material and 2.4 inches in diameter.  The big
problem
is they are listed at over $17 each from the distributors.  I will need 18 of
them eventually.  6 each for this dipole and two more yagis.  That’s a large
price tag, but still cheaper (and better performing) than the commercial
units
available, according to K9YC.

I have (again at the suggestion in the paper by K9YC) sent a request for quit
to Fair-Rite, asking what quantity I would have to buy in order to get “a
decent price”.  It might work out that I could make a large purchase and
offer
kits of toroids to the group.  I’m not looking to make money.  I only want to
have a good choke at the lowest price I can find.

I may put the antenna up with a temporary choke on it and replace it
when/if I
can get the toroids.

I will keep you informed as to what I find.

I appreciate your inputs on this project.  It’s been fun.

Dave, K4TO