How many beads of what type material are needed to construct a choke balun,
using RG303, for a balanced antenna operating 40M-10M?
How many beads for the same thing operating from 80M-10M?
I would like to write it down in my antenna notebook so that I can
hopefully remember how many of what type to keep on hand.
It would appear that there are some differences of opinion (or fact) on the
proper bead composition for this application.
W2FMI in his book "Building and Using Baluns and Ununs" criticizes W2DU for
the use of "lossy high-permeability beads (2500)..."(A permeability of 2500
corresponds to #73 material-N4OO). W2FMI does not specify which material he
thinks would be optimum, but infers that something "lower" would be more
efficient. Perhaps "lower" means something of the order of #43 (850)
material. In another chapter W2FMI suggests that something higher than #61
(125) and 64 (250) is required to obtain the necessary choking reactance.
W8JI has posted his experiences with these devices, but I failed to write
down the information. W1JR did not say in his recent posting what material
he prefers.
Can someone sort this out for me?
INK N4OO
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