Hi Doug,
Glad you're "learning" all this useful stuff. However, it's easy to become
misled by sincere but totally mistaken individuals who haven't followed
through with the necessary comparison research to validate the advice they
espouse.
The "old xyl's tale" of the "rf" or... misnamed "swr" grease to cut the wind
resistance of the coax going up the tower... is just another example of
sincere but total misinformation. It is a perfect example of what can go
wrong with improper research techniques and protocols.
Ask any old-timer and he'll tell you what really happens..... The stuff you
get in tubes and 1/2-pint cans of "rf grease".... REALLY DOES WORK... BUT,
and here is the kicker... ONLY FOR TWO OR THREE WEEKS.
At this point most users have given up testing and don't realize that the
results are rapidly going the other way! Extensive analysis done in
Luxembourg has proved conclusively that the grease at first cuts the wind
resistance significantly but has the nasty propensity of becoming "sticky"
on exposure to UV. The sticky film then traps airborne dust and dirt and
exponentially starts to INCREASE wind resistance.
Microscopic analysis reveals that the surface characteristics of the coax
jacket takes on the look of sandpaper to the impinging air. These entrapped
grains are also naturally hygroscopic... attracting moisture like mad.
Then, when the temperature drops, the moisture freezes- providing a nucleus
for more moisture to build and coat and freeze on the particle underneath.
The result is now obvious... catastrophic ice build-up which not only
increases the surface area and wind resistance of the coax but also the
vertical load factors which might just cause a tower to crumble to it's base
in a mild winter storm.
The coax grease is also responsible for the coax becoming so heavy at times
with ice load that it tears itself from the antenna, connectors and all.
This result is indeed fortunate since only the coax crumples to the ground
thereby "saving" the tower and it's beams.
Now there will be people who'll tell you that the guys in Luxembourg don't
know what they're doing... but I for one believe them... because, what the
hell else is there to do in Luxembourg beside test this stuff. When the last
time anything of significance or importance came out of Luxembourg...
besides a QSL card? So, you know the test must be accurate.
Whatever you do... don't accept reports of test results on face value!
There are conditions which may have been omitted from the test protocols
that may affect the results substantially. The next thing you'll read on
this subject is testimonials from hams who know about the increased wind
resistance and ice loading of the rf grease... but claim the improvement in
transmitted and received signals being in the neighborhood of 2.7dbi is well
worth the downside potential.
You pays your money and you takes your choice!
Good luck in your own testing. Everything I learned on this subject I
learned on April 1, 1968.
73 de Roger, K2JAS
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