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Old August 26th 09, 02:00 PM posted to rec.radio.amateur.antenna
Michael Coslo Michael Coslo is offline
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First recorded activity by RadioBanter: Jun 2006
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Default MFJ-269 Antenna Analyzer experience

Roy Lewallen wrote:


And suppose that these are exactly what our measurement of the cable
said. We measure 21 + j20 at the input end, and conclude that the
impedance of the antenna is 322 - j105 ohms.

But suppose the measurement at the input end was inaccurate by about 5%,
and that the actual input end Z was 22 + j21. Then the load Z is 273 -
j125, about 15% off in R, 20% in X. . .



Thanks Roy,

My knowledge of the matter is at the noobie level, but given that loss
eventually gets you reading only the Z0 of the cable, it's what I
suspected. I hadn't thought about a big mismatch between the cable and
antenna, so there's another data point.


- 73 de Mike N3LI -