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Old June 10th 05, 01:48 PM
 
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Not trying to be silly, but "noise".
She was looking for "non random" noise.
After capture and when broken down by
a fancy math program that I never could
understand, she got, as a younger cousin
said, "pretty graphs".

No kidding, she was lookng for spefic
"singal" and spen 4 years bulding a data
set to demonstrate them. In a lot of ways
she was going to extreme lengths to capture
what I am trying to get rid of.

Pretty damn funny.

She was look at several nearby by stars for
ceratin radio emissions. Ms C isn't crazy,
but after listening to all that nosie for 4 years
she is a little, shall we say, odd.

To me a static crackle is a static crackle.

I tried to mount the 9":1 up in the air but even with
many ferrite beads on the coax down run, I had issues.

By using triax or twin ax, I got rid of a lot of man made noise.
I had the 9:1 one at the top of the support, 20' up a chinese
elm tree, coneected teh input (hi-z) hot to the antenna wire, the
OUTER briad to the low side, the inner braid triax, , or one side
of twinax to one side of the low-z winding to the inner conductor
of the triax, or the other side of the twin ax and at the bottom,
grounded the outer braid to an 8' ground rod.
I used a 1:1 transformer to connect the inner braid and center
conductor of triax, or two windings of twinax to connect to the coax
run to the house.

I did !NOT! carry the antenna ground to the home run coax braid.
I found that when I connected that ground tothe home run coax braid,
my noise floor jumped back up at least 10dB.


I did the initial work at a friend's farm who used to work for the RECC

and has three power poles spaced at 50' intervals with pullys at the
top.
It is a real nice place to do antenna experiments. There are slight but
uniportant diffrecnes betweenthe way triax and twinax worked.

Triax is commonlyused to carry remote TV camera video long
distances and is a inner coaxsial cabel, with another layer of PVC
and a outtter sheild that is electrically isolated. You typically only

ground one end. Twin ax is a coax with 2 center conductors and
was used to carry video as a balanced signal LONG (I helped intsall
one run that is 3 miles long) distances. Both cables come in 50 and
75 Ohm versions. I experimented with 50 and 75 Ohm version of both
and went with 50 ohms, but there was no tmeasurable difference.

75 ohm triax ought to be easy to get as most TV stations are swtiching
from triax and twinax to fibre optics. I have my old original Doty
antenna
in the back yard, and a new, temporary modified Doty with the 9:1 20'
up.

I hope to determine it there is a real difference over the next few
months.
That and solve AM detector issues, local noise issues and improve
my home grounding system. Ms C says it is "marginal".

Too bad I can't win the lottery...of course I would have to buy a
ticket first.

Terry
ntenna system is mu