[Elecraft] Flummoxed about my antenna

[Mike Goldstein]

How do you reply directly to a post?  Beats me ...

A month or so before the 160M test, I finally had my yew tree, which 
was gradually enveloping my Butternut vertical, "put down". I then 
had to open up the coax feed splice to the antenna, so I could use my 
antenna analyzer to help me return the vertical to its original 
tuning characteristics ... all done successfully. I closed up the 
connection with new waterproofing, and checked the antenna 
periodically to ensure it would be ready.

3 weeks before the contest, I found my antenna would not tune 
anywhere! Very strange. I had just renewed the waterproofing on the 
splice, so I didn't think that could be the problem. The antenna has 
been up 8 years, so I spent some hours removing every mechanical 
connection one at a time, cleaning them (and they were grungy!), and 
rebuilding the antenna. Surely that would cure the problem?

Nope, same results. In desperation I ordered a new Buryflex feedline, 
as the line sits on the ground in my backyard (never heard of 
Buryflex before, and the original line is RG213).  Was it new when I 
installed it?  I can't remember!

By the time the new line arrived, our weather window for working on 
antennas had pretty well closed, and the contest was getting closer! 
The antenna was unusable.

Lo and behold, we got a day of sunshine, and 40F temps! Out I go, and 
open the waterproofed connection once again. I'm going to check the 
antenna tuning at the antenna, and the original line looking back 
toward the shack, using a 50 ohm termination.

Well, the antenna still looks good, so the current choke must also be 
good. Measuring back through the coax line, I see an SWR of 1:1, 
which at least indicates to me that the line is usable. Very strange. 
It looks the same when I move the termination to the antenna end, and 
measure the line at the shack end. Stranger and stranger ... in 
desperation, I connect the line back to the splice, and make the same 
measurement again from the shack, and the antenna seems to be 
operating first rate.

So, I tighten up the connection with a wrench, re-waterproof the 
splice, pray to the gods, and check it again, and all is as it was 8 years ago.
No signs of water in the coax, either. I can only assume that the 
splice connection to the coax line somehow became loose or 
disconnected, but it took weeks to do so, after I'd done my 
adjustments.  Didn't feel loose, when I disconnected it.

4 days to the contest, it's all working well - my garden is muddy in 
the extreme at this time of year, so to Hell with replacing the coax 
line.   The original line seems to be working for the moment, and it 
will be a lot more fun to do it next spring!

Later - 200 QSOs in the contest on the weekend, over 7 hours. I heard 
EU, very unusual, and worked down into the Caribbean, and out to SD 
and MT ... and the band was definitely lively.  Sure didn't do any 
harm to clean up that antenna after 8 years, even if it didn't fix 
the original problem!

73 Mike VE3GFN


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