I had hoped that Triax might make a better
feedline. Better as in less noise ingres,
not lower line loss. After experimenting
with a new and temp 80' wire antenna,
with a Minicircuits 9:1 matching and a
Minicicuits 1:1
(see members.aol.com/WA1ION/nrants.pdf for
how the 1:1 is used) and a 90' piece of
Triax I found that Triax helps reduce the
ingress for frequencies below ~1MHz.
It made NO difference above 2MHz. Between
~1MHz and ~2MHz any diference is debatable.
I grounded the outer braid on the Triax
at the transformer/antenna. Using the
diagram in the NRANTS.pdf I found in
earlier experiments that R1/R2 have no
effect. Like the NRANTS diagram, the
shown COAX becomes the inner and ungrounded
shield. I grounded the outer Triax braid
at the base of the antenna with a 8' rod.
At the 1:1 transformer I did not ground or
connector the outer shield at the 1:! end.
The 1:1 transfomrer is located just outside
my radio room and is in a shielded (Altoid tin)
box that is directly grounded. The shield of
the cable that comes into the house is only
grounded at the ground strip in my room.
My ground strip was salvaged from a eletrician
friends junk box and is the grounding busss from
service pannel and is about 1' long, 1" wide and
1/4" thick and has 8 tie points and is connected
to the outside RF ground by 3 parallel 1/2" tinned
braids that are about 3' long. My RF ground is
bonded to the power/telco ground by 1/2" tinned
braid. The power/telco ground is the standard
8' rod.
The RF ground consists of an 8' ground rod,
connected to four 4' ground spikes(2 8' ground rods
cut in half) via 1/4" copper tubing that is brazed
at each end. The copper tubing rdiates away like
finges from the palm of your hand are about 10' away.
The tubbing and top of the ground spikes is about
18" under the soil surface. For this experiment
I laid the feed line on the surface of the earth.
The antenna was suspended at about 15'on one end
and about 30' at the other end, and sagged to about
10' at the middle.

I have found the NRANTS setup to be very good
in reducing noise and is the best antenna setup
I have used so far. Midline 1:1 transformer
really helps reduce noise from the PC used
with my radio to a minimum.

This afternoon a friend is bringing some shielded,
balanced video line and we will see how it behaves.
For this experiment I will use a modified matching
network with R1 halved and placed in series with both
out put legs of T1 (9:1). After that we will test
lamp/zip cord and some high end balanced microphone
cable.
Terry