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Old October 30th 03, 01:59 PM
Yuri Blanarovich
 
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Richard KB7QHC wrote:

This speaks more of simple Resistive heat loss supported by your own
direct observation of:
I fried the loading coil with 600W into Hustler resonator,
melting heat-shrink tubing and wire at the bottom of the coil.


No, it confirms that there is a significant (not negligible) difference in the
current at the bottom vs. top of the coil. Yes, Hustler has small (almost
resistive) wire on 80m resonator. If you trasmit for short period of time (not
enough for heat to equalize) and feel it, or use thermal strips to check
temperature, you would see the taper in the current from bottom to top. It is
in order of 50%, not negligible. Coils in tests are good quality, not
"resistive" wire, current relatively low (100mA) as shown in W9UCW measurements
and pictures.

The point is, if the current was constant or close to it, you would not see the
difference as we see it. Heat rises to the top, if anything the top would be
warmer if the current was constant. If the coil is uniform colenoid, same wire,
diameter (resistance), spacing and it shows difference in heat produced accross
the coil, then we can, using I2R formula, deduct that that current at the
bottom is greater than on the top. W9UCW measurements confirm that, Cecil
explains. Speculations that Earth must be flat might satisfy those reading the
(wrong) books, but will not jive with reality.

Simple way to test it, transmit 100W to 80m Hustler resonator, and feel the
coil. Even insensitive people can feel the significant difference in
temperatures. Put 500W to it for longer period and watch the heatshrink tubing
shrivel from the bottom up. This eliminates all the "errors" with meters to
prove the point.

Yuri, K3BU/m