In a message dated 10/10/00 11:22:02 AM GMT Daylight Time, k7fm@teleport.com
writes:
<< Probably the greatest accuracy is when the load is 50 ohm +j0. As you
depart from that, you will see more and more error. If the purpose is to
end up with 50 + j0, then it does not matter. but, if you are measuring
something which is 336 +123, you may not even be close. I have a large old
GR bridge for that purpose. >>
Even the $5k+ Delta OIB-1 and OIB-3 operating impedance bridges tend to pull
a bit when the reactances start to get really high. I also use a GR-1606A
for critical impedance measurements. The other nice thing about the MFJ is
that I can use it as a signal source to excite the GR bridge when making the
critical measurements. But for getting in the ballpark, the MFJ works fine.
73........de Goose W8AV
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