Antenna Damage from Tornado Near-miss

On the morning of August 4th 2020, a Tropical Storm passed through the Northern Neck area in Virginia. The storm sent an EF-2 tornado through our area in White Stone, starting in the Windmill Point area and traveling about 15.5 miles, passing by Kilmarnock. The tornado missed our house by about 1000 feet, but put two trees on our house. We were relatively lucky, as it only damaged our screened-porch. Some others in the White Stone area were not so lucky. While damage in our community was small, several homes a mile or so away did suffer major damage.

Wire Antennas Down

All of my wire antennas were destroyed and have to be replaced. This is the one time I am glad I do not have any valuable metal antennas or supporting structures. Wire is cheap and falling wire does not do any major damage. My total antenna loss is probably about $ 150. Of course, it will take me weeks to get them reinstalled. I did manage to get my 80 meter Broad-band Dipole installed last week, just in time for the NAQP SSB Contest.

6BTV Vertical Antenna Survives

I have a Vertical mounted on my pier, over the Chesapeake Bay. There is only one set of guys, using parachute cord. It survived with no signs of damage. Crazy how a storm can snap a 36″ diameter pine tree in half, 50 feet away from this vertical, which did not even notice the winds.

Balun Damaged – Internally

I had a 1:1 Balun on my 80 meter Dipole that ended up on the ground after the Storm. I took the cover off, just to see that it was not full of water, bugs, or other surprises. Looked OK, so I put the antenna together with new wire. I hoisted it to about 20 feet and did a quick scan with my Rig Expert antenna analyzer. DEAD! The SWR was insanely high across the 80 meter Band, and most other low HF Frequencies. I brought it down and removed the balun. It had an OPEN on the Ground/Negative labeled side.

Guess I should have looked more closely at this Balun, when I had removed the cover for inspection. On the balanced-side shield terminal, the ground shield had only been “tacked” to the lug with solder. The shield had separated from the lug, and there was no sign of any solder ever being on that lug. Guess it was a cold joint all along. I wrapped some wire around the coax shield and through the lug, and made a strong solder joint. I then scanned again, and the shield side was STILL OPEN!

Looking at the shield connection to the coax connector on the Unbalanced side, the shield was loose inside the lug that had been “soldered” onto the shield. I could move it freely, and could have pulled it right out of the solder lug. Another Cold solder joint. I resoldered that, closed it up, and reinstalled the antenna. Now it again looks like a Broadband 80 meter Dipole. It played perfectly in the NAQP Contest.

Lesson Learned

The forces from falling 35 feet are strong, and can do internal damage to antenna components. I now see that you can get a factory-made balun (or anything else, I guess) with poorly soldered connections. The approach used to build this balun would not have passed a vibration test, but I am sure the design was never subjected to such a test. In the future, any antenna components I buy, will be examined internally, for poor assembly and strengthened if required, before they go into the air.

 

 

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