Well everybody,
I have a great success story to tell you all.I had excellant results on
my 1st attempt at using my new "Free" CATV hardline.Let me outline the
hows and whats of the project.The fittings I ended up fabricating were 1/2 inch
copper couplings soldered to a Amphenol barrel connector.The coupling slid
right over the outside aluminum jacket of the hardline.I cut 2 slits into the
coupling so I could clamp it tight to the cable.I fabricated the fitting as I
was told and also is in an article in the Nov./Dec. 1991 issue of NCJ,written
by
Ray Benny,N6VR.(callsign may have changed,I dont know for sure).
As many of you know,I was pondering over whether to use transformers or
not, to match impedences.That was going to be my 2nd choice had I not had such
great success in tuning my feedlines.Dale,K5MM will be thrilled to hear that I
am not using transformers!!.I used a MFJ 259 antenna analyzer,borrowed from a
fellow contester and friend,N9CK(thanks Steve),to tune the feedlines.I was able
to tune the feedline with a 50 ohm resistor at one end and the analyzer at the
other end and just cut to length to the frequency that I wanted resonant.It
worked excellant.I have my tower with the 40 mtr beam, 80 mtr inv L and 160 inv
L hooked up and finished.I ended up with the main feedline to the tower to be
171 feet.That took me to the top of the tower.This length was perfect for
resonance at 7025 and the 80 mtr DX window of 3790-3800.The 40 mtr beam just
needed a short 5 ft piece of flexible coax to complete the hookup from the
remote antenna switch to the beam.The 80 mtr inv L has a matching network on
the ground so I ran a 50 ft piece of 50 ohm coax to that antenna.My 160 mtr inv
L was not resonant,so, I cut another 50 foot piece of the CATV hardline to go
from the antenna switch to the matching network on the ground for that antenna
and this brought it to resonance in the 1825 region.All of my antennas are
showing flat swr where I prefer to operate and improved power output.I have not
had a chance to hook up the other tower with the tribander yet,but,I have
tuned the coax and if it works as well as the 40 mtr tower I will be very
satisfied with my project.I want to thank everyone for helping me with this
venture.I have learned a great deal and I should be a bit louder in the pileups
and contesting,mentally I feel 10 db louder,Hi Hi.I will let you all know how
the other tower turns out.
Many thanks,Bob WT9Q
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