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Old June 18th 05, 07:56 AM
David Ryeburn
 
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In article ,
Owen wrote:

Indeed. It occurs to me that if one was to try to measure VSWR (say
using a slotted line with probe) on a lossy line operating at high VSWR,
the best estimate would come from finding a minimum, measuring it and
the adjacent maxima and calculating VSWR=(Vmax1+Vmax2)/Vmin/2 so that
the measurement is biassed towards the notional VSWR at the point of the
minimum (the minimum being much more sensitive to line attenuation than
the maxima).


If you think about exponential decay along the line, the geometric mean
sqrt(Vmax1 * Vmax2) would be an even better replacement for Vmax, to use
in the numerator, than the arithmetic mean (Vmax1 * Vmax2)/2.

David, ex-W8EZE

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David Ryeburn

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