As reported here earlier, I recently assembled a Force 12 C-3SS.
The process of building and then installing the antenna took
three days (over two weekends). There were a series of issues
that contributed to the length of time required.
1. The instructions, while long and rather concise, did have
some mistakes and omissions.
I have an early (first production run) of this antenna, and the
manual had some obvious errors and others that were more subtle
(the element dimensions in the drawings didn't seem to match the
actual elements -- especially the 20 meter elements; the
assembly of the feed system is very vague). There was an
incorrect part (stud to hold linear loading elements) that need
re-drilling.
Email to this reflector after my first posting about this
antenna solved most of my problems. Pete, N4ZR, recommended that
I look at the 'Technical Tips' on the Force 12 web site. That
was invaluable, and I hope some of those pictures (especially
the pictures of the feed/balun assembly and 20m reflector) are
put in the manual. Without them I doubt I would have figured it
all out!
2. It took time to formulate my questions to Force 12 in order
to complete the project.
Force 12 told me that I should fax my questions to Tom. Working
in regulatory affairs for a satellite company, I have come to
learn that precise language makes a difference! I took my time
to carefully formulate the questions that I needed answered. I
added drawings where words were inadequate. I am convinced that
the answers I received in the response from Force 12 were far
better than what I may have gotten by way of a telephone call.
The questions were more clearly stated on paper, as I suspect
were the answers.
3. I didn't have much time or help for either aspect of the project.
Building this antenna was different than anything else I'd ever
built (mostly VHF and UHF antennas). My helper was a newly
licensed ham in the neighborhood. With my kids (4 and 6)
running around the backyard, I couldn't complete the assembly
until I was ready to hoist it to my roof immediately after the
antenna was built. So I ended building it in phases.
4. I thought I'd have to have a tree trimmed to fit the antenna
on my roof tower.
After lining up two estimates, we had a fierce thunderstorm
followed two days later by an equally forceful micro burst. A
result of DC's well-known financial and (local) political
problems over the last 10 or so years has left our tree
population in a sorry state. Needless to say, the tree companies
weren't interested in my small job...they showed up after the
antenna went up! As it happened, the trimming needed is quite minimal.
So the antenna went up on Sunday (thanks to master roof climber,
wasp killer and EMT N3OC) and seems to work well. I used a
Wiltron site master to measure the SWR curves and they are what
I *think* they should be (based on similar results emailed to me
by W6FUB and VE3YV/K8HI).
I set the 10m element in its normal' (center) position. The SWR
is too high for my tastes at the lower band edge. Not sure if
I'm going to try and fix that, though.
In the end, it hasn't been such a bad experience. Certainly
better than two recent overseas work trips where the (expensive)
test gear I had used days before in the States failed in front
of high-level regulators whom we've gathered together to
demonstrate our satellite system.
I hope that Force 12 will revise the manual -- fix the obvious
and subtle errors, correct the dimensions and drawings, add more
pictures -- or better, make them line drawings -- and, as others
have stated, include SWR curves.
If anyone's interested in my SWR curves, I'll be happy to email
them out.
73, Eric W3DQ
Washington, DC
wd3q@erols.com
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