Several requests were made for info from my original post so I will attempt
to answer everyone with this reply:
1) my "sailing" record of the 40m-4 was with the antenna u-bolted to a leg
of 25-G at approximately 160 feet-- the antenna still attached to about 18"
of side rail landed all in one piece about 210 feet away from the tower---
i still use this antenna for parts!
2) yes, the 3 element 80m beam is still up ( 4th year now) and working FB
without any mods
3) now to the 40m-4--- these mods will cost just a few buck but well worth
it!
Boom: 1) If you live in a heavy wind/ice area buy a 2 7/8" insert for the
mid-boom area about 20ft. 2) throw away ( or save for a 10M antenna) the
boom support, including the "cube-locks" and add a couple of heavy
turnbuckles and heavy ( 3/8" ) phylistran.
Elements: Before starting to assemble the antenna make sure that the black
lexan insulators have absolutely no cracks!!! If they do return them and
get good ones---
this is a weak link and even the good ones will eventually cause trouble.
Use 3
HTM-380 clamps on each element and do not over tighten any of them. After
proper alignment ( and assembly ) secure each of the HTM-380 clamps with a
stainless screw.
Make sure that the linear loading insulators turn freely on each element.
If they tend to bind use a "rat-tail " file to SLIGHTLY enlarge the holes.(
Hold on to this thought - more later)
While putting all of these element halves together use your BEST mechanics!
Properly tighten all connections! Buy a few extra lock washers- double nut
everything!!! ( $5.00 of extra locknuts and starwashers will save you a
repair later!)
BALUN: throw away the one supplied and construct one of high quality RG-8
( per directions with the 40m-4)
Now , you have the antenna all together! You have followed the element
chart exactly and all dimensions are perfect. Let the antenna set 2-3
days! Now go over every connection again . After making sure that all
connections are tight, double-nuts etc, apply a liberal coat of GE RTV
silicon glue to every connection.
Place each of the linear loading insulators in their exact location making
sure that none of them bind! ( If binding is a problem fix it now--- it
will cause trouble later)
Approximately 1/2" on each side of every linear loading insulator wrap the
element with 3-4 turns of high quality electrical tape ( this will prevent
the insulators from
moving ).
Most of this I have learned from playing with 4 different 40m-4 antennas at
my qth... some of the "tricks" came from Hank- K4FU. I hope this has
helped.... it comes with no gurantee and especially since im now on my 2nd
bottle of Chardonnay.
Have fun guys-- if it falls fix it
73
BUD- K4ISV
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