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You are using a thermocouple which is sensitive to heat, the heat of coil loss will inflate the reading. You have twice offered heat at the bottom of the coils that correlate strongly with inflated current values from a caloric sensor. You have no other thermocouple data supporting the nature of the current distribution, just the isolated section you find attractive. Put simply, your measurements have no reference (readings from the entire length of the radiator). The bottom meter is below the coil, so there is no heat heating up the thermocoupled meter. If you insert the meters some distance away from the coil, you would see the corresponding readings showing the difference between the top and bottom. Arguments that heat or magnetic field affect the thermocouple RF ammeters are just not realistic. You went to some trouble to offer testimonial from reference sources on the nature of that distribution, but you did not measure it confirm your testing. Two readings in isolation do not prove you have 100mA into the bottom when there is only one reading below the coil. I did just rough test with one of my meters (has 8 A), flipping the coil and I can see some deflection at the bottom and none at the top with 100 W into the antenna. W9UCW et al did hundreds of measurements and showed just some examples. If you are not interested in obtaining those remaining readings of that current distribution, then you have a poor case. My "case" is to bring this to attention of those who are still "knowing" that the current in loading coils is the same at both ends. If they doubt, they can do their own measurements and see what it is, or show us where we are wrong. Again, ON4UN in his Low Band DXing book has it right, ARRL Antenna Book has it wrong and is perpetuating 50 year old misconception. Just MEASURE or FEEL it! 73's Richard Clark, KB7QHC Yuri, K3BU/m |
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Yuri Blanarovich wrote:
My "case" is to bring this to attention of those who are still "knowing" that the current in loading coils is the same at both ends. The current can be the same at both ends if the coil is positioned at a current minimum or current maximum point which is NOT the case with mobile antennas. The key to understanding is to recognize that the coil causes the opposite phase change in the forward current as it does in the reflected current so they *cannot* track each other through the coil. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
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