I have never tried tilting the a beam up. It seems like a lot of trouble,
especially with a long boom and I would not be confident that it is still
tuned properly. It is quite easy to pull a beam up the side of a tower
about a wavelength high and take measurements though 1/2 wl multiples of
coax and then bring it back down to make any adjustments. I have done this
completely by myself many times and my antennas have a nearly perfect SWR
curve when mounted.
John KK9A
From: "Ed Sawyer"
Date: Fri, 23 Feb 2018 05:57:39 -0500
I don't find that the "point the beam skyward" method works that well on 40M
beams for doing the initial SWR test. The typical 40M beam is a loaded
element and on a boom that is usually 20 - 24 ft long. 24ft high is not
enough to have the DE up and away from the ground.
It will tell you its not shorted or open but as to whether its tuned right,
it needs to be in the air.30 to 40 ft up is usually a minimum and even then,
the SWR low point will shift by another 20 - 50khz by the time its up at 70
- 100 ft in my experience.
Ed N1UR
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