On Mon, 2 Feb 2004 09:33:07 -0500, Tom Rauch wrote:
>People can measure things like this any way they like. I use a 50 ohm
>network analyzer that has a 50 ohm source and load, but some CE tests or "do
>it yourself" tests use other methods.
Tom has hit this nail straight on the head (as usual). The problem is
comparable to measuring the filtering characteristics of power line
filters -- neither the standards for measurement nor the available test
correspond very well to real world application of the product being
described. Performance near resonance is one thing, performance a few
percent resonance can be an entirely different kettle of fish.
IMO, this makes it more critical than ever that the phrysical and
electrical construction of the product be completely and accurately
disclosed. I buy a commercially manufactured balun because I don't have
time or resources to design, build, and test a better one, put it in a
really weatherproof package, etc.
I need to buy some baluns for a HF antenna farm I'm planning for a
mountaintop QTH out west. They will all be for wire antennas, and the
QTH, at 3,000 ft, gets some serious icing. The EF-1, EF-2, and EF-3
series of baluns look like good products. Are they? Has anyone tested
them? Anything else I should consider? At least some of these
antennas will be fans (i.e., multiple elements for different bands), so
attachment of wire is an issue.
Jim Brown K9YC
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|