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Field Day Preps… Antenna Masts

 

Field Day Preps… Antenna Masts

Filed in Antennas on Jul.02, 2009

My good friend from Omaha, John (wb0who) arrived on Friday, June 26th to participate in Field Day and get a tour of the Ranch.
The first order of business was to finish getting the guy lines attached to the towers, and get the towers in the air.

We attached 4"³ or 5" eyelets (depending on which way we were going through the 2x4s) at the top of the masts to support the ends and center of the dipole. Then we attached similar eyelets about 5 feet below the top of the masts for guy wire supports. These were placed so that the guy wires would pull in the general opposite direction from the antenna wires.


Attaching the guy wire eye bolts

As we were raising the first mast, a thunderstorm blew in, and it started raining pretty hard. We took shelter under the shade tarp for awhile, then eventually moved to the LittleHouse to gain a little safety from lightning.


Rain coming down

About an hour later, we were able to resume erecting the antenna masts. The only damage was a stepladder blown over by the wind. We felt pretty lucky that the strong winds didn't do anything to the unguyed pole that was up in the air.


After the storm

We ran a rope up through the top eyelet on the end masts, to be used to pull up the ends of the dipole antenna. Then we ran a rope up and through the guy eye bolts to be used as a guy line. The two ends of the guy line were attached to either fence-posts or the bottom of nearby convenient trees.


First mast guyed to fence-posts

The second end mast was in a little denser area of trees, so we were able to use the lower portion of the trees as guy anchors.


Erecting the second mast

We pulled the guy lines enough to bend the top of the mast slightly, expecting that when we pulled the dipole tight, it would put pressure in the opposite direction.


Guying the second mast

At this point, we left the center mast down, and went off to construct the 80-meter doublet antenna. (next post)

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