[TowerTalk] Antenna Grease--Deficiencies and Remedies

[George Bethea]

Up until recently, (3 yrs ago) I ran a KT34XA for approximately 20 years, at
a qth 900 ft from the Gulf of Mexico in Gulfport, Ms. The antenna was
exposed to direct salt spray, high humidity, massive UV, and 4 hurricanes.
It performed very well on 10 and 20 meters and was fair on 15 meters. I
worked well over 320 countries on it from that location. I had to rebuild it
about every 3 to 5 years, due to corrosion causing bad connections in the
element  joints, as well as the linear loading assemblies and strap points
on the driven elements. I also changed the lexan element to boom brackets
three times during my ownership of it. Cracks would appear in them even when
bolts were carefully torqued to factory specs.
On the last rebuild I replaced the boom as the contact area of the boom to
element brackets corroded so badly that porosities formed under the brackets
causing holes in the tubing degrading structural integrity.
The copper based paste, (identified in my original manual as Penetrox) would
dry and cause mechanical binding and allow corrosion to form in the joints
and make for a tedious disassembly. Testing showed high resistance and
capacitive joints when this occurred. Rivets used in the element joints and
at the strap points, using Noalox instead of the supplied Penetrox, as well
as sealing the strap points with elastomeric marine sealer, went a long way
in reducing problems experienced earlier. I also found that using a 1/4 inch
pop rivet instead of the stainless screw that pins the stainless compression
clamp at the boom to element bracket would allow the elements to shear the
rivet and rotate on the boom, and in my case, eliminated element damage in
high winds during fierce gales, (90mph gusts) as well as hurricanes of
minimal status ( under 100mph straight line winds). 4 years ago I moved to
24 acres 40 miles north of the coast, and reinstalled the KT34XA on a 70 ft
crankup. After hurricane Georges hit us in 1998, I rebuilt it again and gave
it to a close friend. I replaced it with a  Force12 C31XR. I am extremely
happy with the new antenna, and I do not regret purchasing it one bit. I
dropped it recently just to check it out and I  found it to be just as sound
as the day I put it up, 3 years ago. How I feel they compare is for another
posting however. I hope this helps you and I also apologize for this lengthy
message.
                                                                   73, God
Bless
                                                                   George
K5JZ k5jz@mdxa.org


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