March 15th 06, 05:56 AM
posted to rec.radio.amateur.antenna
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Current through coils
K7ITM wrote:
John P. wrote, "A network analyzer is way beyond my budget."
Though I'd love for you to buy a nice new Agilent Vector Network
Analyzer, I have to say that for things up through low VHF at least,
the very economical project at
http://users.adelphia.net/~n2pk/index.html is well worth looking at.
The performance, when properly calibrated, needs no apologies, for
sure. Paul is one of the Good Guys in ham radio, and not just for
making this project available.
One of Tom's links probably won't work for you, but I'd highly
recommend some of the ap notes you can find after a somewhat diligent
search. I'm sorry to say that the search engine on the Agilent web
site is a poor relative of Google, but you should be able to find these
two ap notes the
Agilent AN 1287-1: Understanding the Fundamental Principles of Vector
Network Analysis
Agilent 1291-1B: 10 Hints for Making Better Network Analysis
Measurements.
They are in PDF files, and I just saved a copy of each...just in case
you can't find them.
A Google search on phrases like "network analysis application note" and
"VNA application note" should yield some interesting things. Here's
one thing I found, which has links to others:
http://na.tm.agilent.com/vnahelp/appnotes.html
Finally, there is an old HP ap note on S-parameters that you should try
to find. It _may_ be on the Agilent web site, but if not, a Google
search will probably turn it up. Though a Vector Network Analyzer does
not necessarily have to do S-parameter measurements, the 8753 is set up
to do them as its fundamental measurement, and they are generally
useful in making higher frequency measurements, since the standard
methodology in the industry is to use S parameters to characterize both
passive and active devices. If you look at network analyzers on eBay,
you may see ones offered without the S-parameter test set, and you can
find the S-parameter test sets offered separately; that's all fine so
long as you understand what you are looking at.
Thank you for all this useful information.
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