Many thanks to all of you that responded to my email several weeks ago
requesting suggestions on the assembly of a Force 12 C3S. I apologize for
not responding to each of you or to the list sooner...
My antenna arrived on schedule from Force 12 but then it had to sit in its
box because of bad weather over several weekends. Bummer. The weather
and my schedule finally "cleared" last weekend so I could assemble the
antenna on the ground beneath my tower. I had to wait until yesterday to
actually get the antenna onto my tower.
As others suggested, I assembled my antenna elements using 2 saw horses to
support the ends. I alternately sat or kneeled between the saw horses to
do my pop riveting. I found the assembly to be very easy and had no
problems what so ever. All rivet holes lined up. No re-drilling was
needed. The instruction manual was clear but, after reading it through
once and assembling the first element, it was largely not needed!
My only complaint with initial performance measurements of the C3S is
related to the 10m band. During assembly, the 10m and 15m driver elements'
lengths can be adjusted slightly by changing the length of the outer-most
section of tubing on each side of the elements. Based on advice and
comments from this list, I used the longest possible adjustment for both
drivers. Unfortunately, the adjustments for 10m only shifted the lower
"under 2.0 SWR" band edge down to around 28.200. I'll need a tuner for the
bottom of the CW band... I debated on whether to pull the tubing out more
and drill new rivet holes but elected not to. I wish the length of the
last 10m driver sections had just a couple more inches of tubing to make
that adjustment possible! On the positive side, the antenna stays under an
SWR of 2.0 well up into the 29MHz end of the 10m band -- making it
fantastic for the SSB portion of the band. Since others have made similar
comments about this adjustment, it might be a good "product improvement"
for Force 12 to consider. No tuner is needed at all on 20 and 15 and the
SWR on 17 and 12 meters is not that bad either :-)
I used an inverted V of rope from the top of the tower as a guide to "tram"
the antenna to the top. That worked like a charm -- as did Force 12's easy
mounting bolt mechanism on the boom to mast bracket.
Thanks again for all of your suggestions about the C3S. It looks like it
will be a great antenna for me and I am looking forward to giving it a real
workout in the coming days and weeks!
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