Thank you to all the email's received re my use of trailer balls for a
spark gap..It is a simple answer to a big problem and it works..
It pays to think outside the box at times when presented with a problem
and be a bit innovative..
I also use a trailer ball at the bottom of the 90 foot mast and on my
160 meter vertical antenna...Using triangular mast section I have
tapered the three bottom sides of a triangular section and welded a
trailer ball on the bottom ...I used a 66kv three skirted Electric
supply insulator which has a galvanised metal plate on the top with four
1/2 inch studs about 4 inches long....I cut out a 1/2 inch metal plate
to fit on top of the insulator mounting plate..I then used a piece of
heavy 2 inch tube 3 inches long and welded it to my mounting plate..I
reinforced the tubing on four sides with some 1/2 inch plate....This
mounting socket is strong....I drilled a couple of holes at the bottom
of the tube as a water drain and also added a grease nipple....I then
bolted this assembly on to the insulator top plate...The insulator is in
a 2 cubic meter concrete block in the ground with four copper clad earth
rods....The mast with the trailer ball sits into my home made socket and
is well insulated from the ground..
So there you are....All you need to do is use the old noggin and many
mechanical problems are easily solved...
73....Bob..VK3ZL..
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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