(de KT4ZX - Lee - leewells@lexmark.com)
First off I want to thank everyone that helped out with my Inv. L questions.
It really played well this weekend in the contest (turned in 555 QSO's in 16
hours with 100 watts). I'm getting a summary together of all the responses
I received....I'll post it to the reflector later in case some other newbies
could use the info.
I was trying to get two 2-wire beverages up and running for the contest. We'll
I finally got one hooked up early Sunday morning when things got kinda boring in
the contest. (Yeah the neighbors probably think I'm crazy running around
outside
in the middle of the night with a flashlight and a roll of coax) It definetly
has a better signal to noise ratio than the Inv. L, but I can't really see
any directivity when switching between the front & back.
Its 450+ feet long, made with 14 gage stranded copper wire, with 6 inch
spacing between the two wires. Its about 7-8 feet above the ground, using
trees as supports. The last 50 feet slope down to ground level.
I followed ON4UN's book to design the transformers. I ended up using toroids
with a ui of 2000 (AL of about 1200). I ended up using 17 turns for the
primary,
and about 60 turns on the secondary for the one connected to the beverage wires,
and 40 some turns (trying to recall from memory here) on the secondary of the
other one. I'm using a small relay to switch between front & back, and then
just
running one coax line back to the shack. I'm using 4ft lengths of 3/4" copper
pipe driven into the ground at both ends of the beverage. I've probably
only got 3 feet in the ground....couldn't drive them any further (hit rock).
When I switch from the Inv.L to the beverage, the noise level drops from
s5 to s0 (cool!), and signals seem to drop about 20db? (S9+20 to S9). This
was with stateside stations, so I'm guessing maybe the wave angle was too high
to really take advantage of the beverage???????? I can't see any difference
when
I switch from the front to back (slight increase in noise level in one
direction).
I listened to a couple EU stations last night, and still couldn't tell any
difference
when switching front to back. Do I need a NE/SW beverage for EU, or should the
E/W one work okay?
There does seem to be noticeable difference Front to side. I can barely hear
stations to the north and south off of the beverage.
So what should I expect from this setup??? Are there some beginner errors that
I might
have made??? Any ideas on where to start looking????
Thanks again!!!
--Lee KT4ZX
---
Lee Wells - KT4ZX
leewells@lexmark.com
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