For 50 MHz, you want two or three turns through a 1-inch long core and
two turns through a 2-inch core,. and for maximum noise suppression, you
will want at least three of these multi-turn chokes in series along the
line, close to the feedpoint. The reason you need multiple chokes in
series is that you only need 2-3 turns to put the resonance at 50 MHz,
so you haven't got much benefit from N-squared. Fair-Rite #43 and #31
are roughly equivalent at 50 MHz.
73, Jim K9YC
## what do u mean by a 1" long core ? Does this mean 2.4" OD x 1/2" thick
torroids used... and 2 of em stacked ? Is a 2 " core consist of 4 x torroids
## It can't be ID. You won't fit 9913 through a 1" ID very easily..well
maybe u can?
How far apart is each of the 3 x chokes to be spaced from each other ? How
propose to keep this mess away from the boom..and or mast ?? I think I would
all of them to be at least one outer loop diam away from metal. If they are
metal, the C between coax braid and boom/mast/tower will surely screw up the
You would end up lowering their resonant freq. The stray C would parallel
chokes..and probably increase the choking Z... but at a lower freq. It might
be broad enough
peak to still cover 6m.
## In some cases, you can't hang em below a boom...if the connections are on
top of the boom.
Even if hung below a boom, I would not want them flapping in the breeze.
What's the fix ?
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