In a message dated 27/02/2005 22:27:11 GMT Standard Time,
david.kirkby@onetel.net writes:
My guess is that the software in
modern VNAs can take this into account, but I might well be wrong. I'm
sure there will be an Agilent application note (I mean sales literature)
on this!!
It's interesting that even with one of their latest digitally corrected
doo-dads just back from calibration, you can still get the trace going outside
the periphery of the Smith chart even after calibrating with the short and the
open. Admittedly, that was with a rather wicked load of 62pF in series with
1nH and 0.3 Ohms at 400 MHz - a small patch antenna - and even higher it got
worse.
Hartshorn's 'Radio Frequency Measurements' of 1940 is still worth
reading..........
73
Peter G3RZP
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