[TowerTalk] Antenna Grease--Deficiencies and Remedies

[K7GCO@aol.com]

Right On Ken.  Any aluminum particles inside the joint do no good as there is 
no RF there.  Only at the thin ring of conduction at the diameter step up 
where the RF jumps the joint would any particles have any value however 
small.  I use silicone grease on all connectors and bolts.  Glad to see a 
source for it is made available for everyone.  Anti Seize does seem to 
weather like Silicone.  All one has to do is measure the joint impedance 
years later to see how it's working.  K&GCO

In a message dated 6/26/00 12:16:07 PM Pacific Daylight Time, calav@flash.net 
writes:<< 
 Gentlemen:  I've been following this thread for some time now.  Please 
consider
 the following:  What is put into aluminum antenna element joints serves 2
 purposes. First, lubrication for assembly and disassembly.  Second, and most
 importantly, it protects the connection by excluding moisture and air at the
 points of contact.
 
 Contact between the pieces will occur between 2 or more points, depending on
 how the pieces are fastened.  It is unnecessary to include metal particles in
 the formulation to make a good connection.  Some of the commercial 
formulations
 (e.g. NOALOX, Penetrox, etc.) that have been mentioned (and even used by
 reputable manufacturers) are intended for electrical wiring.  The antenna
 environment is a different, much tougher ball game.  If the carrier of these
 metal-loaded formulations happens to be silicone-based and is thick enough,
 there is little or no problem; if it is petroleum-based, it is quite likely 
to
 be washed away, leaving a dissimilar metals problem.  (The copper-loaded
 compounds, e.g. Penetrox B, can be really bad news)
 
 What to do:
 Simplify the problem; just use a thick silicone grease.  It has proven itself
 in very harsh environments.  BTW, it is also the goop-of-choice to put inside
 connectors such as PL-259's to exclude moisture.
 
 Where to get it:
  Thick silicone grease is available as High-Vacuum grease, a Dow-Corning
 product, from scientific supply houses.
 
 GC (formerly General Cement) packs it in small tubes, which are available
 through electronic supply houses; Newark, Allied, etc..
 
 My company, CAL-AV Labs., supplies it in 1/4 oz. containers as part of the
 assembly kits sold with our antennas; we would be happy to sell the grease
 packs alone if you can not find them locally. (cal-av.com)
 
 It is also available at SCUBA diving shops, typically in 1/4 and 1 1/2 oz.
 packs or tubes.
 
 Sincerely,  Ken K6HPX
 
 
 
 wbh3@daimlerchrysler.com wrote:
 
 > FWIW when I built my  kt34-xa about 7 years ago, KLM supplied a little can
 > of  copper-colored paste to put on the joints.    After a move and whenn I
 > was reassembling the end units I found this paste had turned very solid and
 > seemed to be a good insulator as the resistance checks I made on each
 > element end were very high.  Don't know what KLM used but I don't think it
 > was very good stuff.
 >
 > Bill Haselmire  WX8S >>

--
FAQ on WWW:               http://www.contesting.com/FAQ/towertalk
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com