On Wed, 19 May 2010 13:17:43 -0700, Jim Thomson wrote:
>You can`t get water into em.. and you can`t blow them up. The EB1 and EB2
>baluns are excellent as well.
"Excellent" is a wild exageration with respect to these so-called "baluns,"
which are nothing more than simple-minded "string of beads" common mode
chokes. True that you probably can't blow them up with the illegal power that
you like to run, but they aren't very effective as common mode chokes either.
Manufacturer's published data is quite inferior to what any ham can make by
winding multiple turns of RG8 or RG11 through #31 toroids and they are VERY
conservatively rated for max legal ham power. Detailed instructions and
MEASURED data are on my website in http://audiosystemsgroup.com/RFI-Ham.pdf
As to "hams are cheap" -- yes we are, but we are also stupid, buying into
advertising claims, and buying inferior junk from companies run by salesmen
that know nothing but advertise in QST for 40 years. The common mode chokes
described in my tutorial (cited above) are fully documented, and the tutorial
completely describes how they work. And I'm not selling anything! The cheap
junk you buy from salesmen like Amidon, Palomar, and their ilk is completely
undocumented and vastly inferior. They re-sell Fair-Rite parts at huge mark-
ups (4-5X cost), but disguise that fact by creating their own new part
numbers. That so-called technical data on their websites is next to useless!
73,
Jim K9YC
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