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Old October 24th 13, 01:10 PM posted to rec.radio.amateur.antenna
W5DXP W5DXP is offline
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Default Gamma Matching Question

On Thursday, October 24, 2013 5:54:05 AM UTC-5, J.B. Wood wrote:
So the above statements don't make sense.


I agree that the E/M ratio for far field signals in space is a constant. That doesn't prohibit a receiving antenna from creating its own unique near-field conditions and altering that ratio just as there is nothing prohibiting a load from altering the E/M ratio that exists in a transmission line. In fact, the E/M ratio must necessarily be altered at impedance discontinuities.

Example: Two different antennas are receiving the same signal and indicating the same signal level. As a human walks close to the two antennas, the received signal strength of one antenna changes radically while the received signal strength of the other is affected by only a small amount. If both antennas were *accepting* the same fixed far-field E/M ratio, a human body should have the same effect on both antennas but we can demonstrate that it doesn't.
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73, Cecil, w5dxp.com