[TowerTalk] Stacked tri-banders vs. Single mono-banders

[Steve Zettel]

So Tom,

Several questions about the 10M add-on reflectors for the C-3:

Your suggestions about rebalancing the C-3E to minimize wind torque with
the additional element?

Will this create any geometry problems for someone who wishes to sidemount
a C-3E on a ringrotator or swinging sidearm mount?

Do you have a best-guess estimate for the new wind load and weight of the C-3E?

Most importantly: How much and how do I order! (I have three of your C-3's
on the ground right now, and this would be a great time for me to make the
modifications!).

Thanks for your time, good luck with your cold and the move.

Steve Zettel  KJ7CH
near Libby, MT  USA

>Good morning, Pete.
>
>Have been off the electronic highway for a few days with a bad cold, plus,
>we are moving this facility. Have been in that process for about 5 weeks.
>Had forgotten how tough it is to move, especially when everything is so
>heavy!
>
>You might be interested in an enhanced C-3 that I have been using for
>several months. The spacing for good gain from a pair of C-3's on 20 and 15
>is too wide for 10. Although it is a good set-up, I thought the C-3 could be
>"encouraged" to do better in a stack on 10 mtrs. To do this, it needed more
>gain on 10 mtrs to work with the wide vertical spacing. So, I added a 10 mtr
>refelctor to a stock C-3. This increased the forward gain on 10 mtrs by
>about 1dB, which makes the typical stacking distances much better for 10.
>The F/B is also increased to more than 20 dB on 10 mtrs and the feed system
>remains as before. The only change was to add the 10 mtr reflector.
>
>I called the "new" C-3 the "C-3E" and it has been in operation for about a
>half year - just to be sure it is doing what we think it should! (This
>configuration does lower the 12 mtr gain by about a dB, but that was a fair
>trade for the primary purpose.) The added element is on a special bracket
>that screws to the boom with four set screws. The element under the boom
>captures the boom and it has held up during several severe winter storms
>here.
>
>If you want to give it a try, let us know!
>
>By the way, it is possible to model a separate 10 mtr antenna between a pair
>of C-3's. When things settle down a little from this move, I can look into
>it. If you need a computer model of anything, let us know.
>
>Have a good day and 73,
>			Tom, N6BT
>			Force 12 Antennas and Systems
>			(Home Page   http://www.QTH.com/force12 )



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