I don't think it's unreasonable to discuss their performance, and
consider the findings Yuri has presented as being both reasonable and
viable.

73, Jim AC6XG


I am just amazed that with all the "theoretical" arguing going on, why none of
the "learned" experts measure, answer or explain the following REAL effects or
show where I (we) are wrong:

We are assuming quarter wave electrical (90 deg) antenna with loading coil
inserted from 50 - 70% of the radiator length.

1. As I mentioned and got only fuzzy arguments (poor coils, metal caps, poor
connection, which do not jive with observations), having let's say 80m mobile
Hustler antenna (many of them around) with coil. Put 100W to it (no
obstructions, meters, things to detune it) for about 30 secs. Go feel the coil,
or if you have thermal strips, watch the color from bottom to top. You will
notice warmer bottom. Put 500W to it, you will "reshrink" the tubing,
heatshrink tubing will start curling from the bottom, insulation on wire will
start blistering. I have done it, I saw it, I melted the bottom of the coil.
K0PP is sending picture of similarly fried Minooka Special. Why coils melt at
the bottom and not all along if the current is uniform across the coil?
Explanation: Uniform coil, with uniform wire, on uniform form, same caps on top
and bottom, the resistance is the same along the coil. If R is the same, and
there is more heat developed in part of the coil, then according to I2R
formula, current MUST be HIGHER in the part of the coil that heats more - at
the bottom. If the current is higher at the bottom part of the coil, it cannot
be the SAME at both ends.
Do not believe me? Everybody can do the test with mobile coil and verify it.
You don't need meters and nothing disturbs the setup. This demonstartes that
current is not uniform accross the coil, it larger at the bottom than on top.
Where are we wrong here?

2. As I quoted on my page http://www.k3bu.us/loadingcoils.htm results of W9UCW
test and measurements, Barry measured in the controlled environment, (60
radials, good coil, RF ammeters) that current in loading coil varies between
top and bottom in the range of 40 - 60%,. which confirms the effect described
above and puts some figures on it. It was done on different bands, with
different positions of the coil and generally follows the pattern. RF ammeters
are designed for this particular type of measurements. We get the same
conclusion and confirm the effect - the current in the loading coil varies
across the coil, it is not the same.
What is wrong with those measurements and results? Again anyone can verify
them. Did anyone measured anything different?

3. Lets look at the RF choke. Coil the piece of coax into a coil with enough
inductance to suppress RF current. Is the current same at both ends?

4. W9UCW used toroid loading coil and got the same results. How could that be?
It was MEASURED not "figured" out.

5. Cecil explained the reflected wave situation and delay in the coil, which
supports and explains the mechanism of the phenomena.

6. ON4UN in his Low Band DXing book for years has shown and explained the
distribution of current in various configurations of loading coils, hats, stubs
and clearly shows that current across the coil decreases in proportion to the
electrical degrees of the radiator that it replaces. Where is he wrong? Another
engineer that "knows nothing"?

7. How could it be if the voltage (neon bulb test) is increasing along the coil
towards the top, current has to be decreasing.

Can we see some other (better) measurements, anyone?
Or is all the above fantasy, because EZNEC says so?
Can we have some REASONS instead of ridicule? Point by point please.

Yuri, K3BU.us