October 24th 13, 01:57 PM
posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Sep 2013
Posts: 62
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Gamma Matching Question
On 10/24/2013 08:10 AM, W5DXP wrote:
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
No
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J. B. Wood e-mail:
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