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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