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John Smith wrote:
"The loading coil acts as the lumped constant that it is, and disregarding losses and coil radiation, maintains the same current flow throughout. This statement is somewhat misleading. A standing-wave antenna is somewhat like a transmission line with standing waves. There are TWO component currents in a standing wave antenna, forward and reflected. The total current is the phasor sum of those two currents. Even if the forward current were constant and the reflected current were constant, the total current changes because of the phase shift between the forward current phase and reflected current phase as these two phases are changing in opposite directions. For instance, given a 1/4WL ground plane vertical, the forward current and reflected current are in phase at the feedpoint, thus resulting in high current. At the tip top of the 1/4WL ground plane, the reflected current is 180 degrees out of phase with the forward current and their phasor sum is zero at that point. -- 73, Cecil, W5DXP ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- |
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