Topband: 160 Loaded Vertical Antennas(Barry, W9UCW)

B. Clark k1fz at prexar.com
Sat May 17 11:22:14 EDT 2003


Barry,

Some years ago I suspected that what you found was true.  My thinking at the time
was, as in an antenna,
when the voltage was increasing, the current was decreasing in my slightly long
loading  coil.  I made some crude test with a neon lamp to confirm voltage taper
of a few coils in my center loaded 75 meter mobil antenna. Then did some further
test with a coil wound  to allow some turns  loose enough to get my Palomar
"clamp" on RF Amp meter connected.   Q dope held the turns in place to some
extent. Right this is crude and measuring at the loose turns did cause detuning
which probably added other flaws to the test. I did retune to minimum VSWR each
time.
My coils were made at a Radio Station where I worked.  I used Tivar 100 as a
form. 1.5 x 11 inches.
The results were, as the voltage was increasing  going up the coil , the current
was decreasing.  I rewound the coil with larger wire size at the bottom and
tapered to smaller sizes up to the top of the coil.;. Feeling the coil after a
long transmission with my hand made me believe the heating was about the same
along the coil
No scientific thermometer used- It would have been possible to use a laser
device, if I had one.   ..

I wrote the taper coil antenna  up and sent it to a popular Radio Publication
which they promptly rejected.
Return current difference may be from the capacitance to the car/earth ground .
This could vary much as to installation.

We have to be free to try new ideas. To perform test and compare results and
challenge what is accepted today.
If not,  we could be still in the Spark Radio days. Maybe pre spark days.. ( : -}

Who was it that said the Bumble Bee is unable to fly.?  (The shadow knows)

Lets keep it light, do more testing,  and advance our knowledge.

73
Bruce-K1FZ





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