I have asked my resident experts (U know who u r.) and added my own unschooled
opinion.
For the three band range (20-10) it’s really trivial.
Going on down to 30 and 40 is only slightly more tricky.
The ARRL Antenna Book deals with this quite concisely and gives winding data
for the “best” chokes for each situation.
Looking a little deeper, they say that if the coax goes down the mast, so it
doesn’t pick up and reradiate a lot of energy (which compromises the pattern),
the balun isn’t really needed. So maybe someone will swing some patterns
with and without the choke, for us?
My own take is that after hearing a lot of talk, much of it BS, and being
exposed to a lot of colorful ads, we have developed a “need” that far
overshadows reality.
And if the coax choke works, why on earth would one want to spend $50-$100,
which will buy a LOT of beer, on $10 worth of stuff crammed into a little box
AND four more connectors to get wet?
I think there’s a real possibility that the losses in the fancy balun, not to
mention poor ones, may be more of a problem than the pattern distortion caused
by not having one.
EZNEC is absolutely astonishing and a wonderful thing, but you can’t let it
wind you up over a couple of dB when you are dealing with propagation ranging
over 60 dB!
Isn’t it amazing that the $18,000 Hilberling had to go back to the factory?
Of course this is a simpleminded argument, so it should be easy to show why
it’s incorrect, right?
Wilson
W4BOH
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