I built my C4XL as best I could exactly per the directions. Foolishly I did
not check it out on the ground. I should have! I set it up for 7.030 MHz, but
I found that it actually resonated at 7.130 when checked after installation.
At that point I was able to reach the 40 meter driver from the mast and
lengthened the loading wire jumper points and was able to bring it down to
7.050. But what happened was this: Whereas at the original set up it had an
SWR curve about what Force-12 described in the manual (actually about 100 KHz
wide at 2:1 SWR points) when I lowered the driver to 7.050 the lowest SWR was
1.8:1 and went up from there. Needless to say the bandwidth was dreadful. I
attribute this to not being able to retune the reflector. It would be
impossible to get to the reflector with the antenna mounted on the tower. Had
I been able to, I trust if I could have gotten it tuned to about 6850 Khz all
would have been well.
With time running out for antenna work I made a snap decision to pull it down,
remove the 40 meter components and simply use it as a tri band beam (20/15/10)
where it is perfectly adequate.
I have saved the 40 meter part and next spring hope to put it up as a separate
2 element 40 meter beam.
I cannot really tell you what to do unfortunately, except this, you had better
tune it up on the ground to your satisfaction or you will be taking it down
again. Possibly you can tilt it and get to the 40 meter reflector on the tower
and retune it, but plan on it being a multi step process.
I would say this is my only complaint. Its hard to tune. Others who have this
type of antenna have had similar tuning problems. Once they got it tuned they
have been happy.
Keep one thing in mind, this is a CW or Phone antenna for 40, not both. Thats
my opinion.
Ron N5IN
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