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[TowerTalk] Ferrite bead mixes?

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Subject: [TowerTalk] Ferrite bead mixes?
From: k4ro@music-city.tdec.state.tn.us (k4ro@music-city.tdec.state.tn.us)
Date: Mon, 5 Jan 1998 19:19:35 -0600 (CST)
I know some of this was hashed around in the past, but I could
not find a definitive conclusion anywhere.  What is the best mix
of beads to use on the 6 HF contest bands?  Here's is what I've
gathered so far:

- Type 77 chokes better than 43, epsecially at lower frequencies

- Because it chokes better, 77 gets warmer, sometimes apparently
  to the point of damaging coax

- Sometimes a teflon coax pigtail is used to deal with the heating
  (but this adds yet another connector junction to the feed system...)

- Some have proposed the idea of mixing type 43 and 77 beads together

- Six (6) beads seems to be the nominal number used at a feedpoint,
  with sometimes even higher numbers on 160 & 80.

Questions:

Is six beads a good number to use?  What do you use for which bands? 

Has anyone used both type 43 and type 77 beads on HF, and can offer 
a comparative analysis?

If mixing the types, what would be the best method and numbers?  

Some possibilities: a) three #43 beads right at the feedpoint with 
three #77 beads right benind it (43-43-43-77-77-77) or b) six mixed
"interlaced"  beads (43-77-43-77-43-77.)

Tracy at Amidon had no suggestions, and their WWW page was not 
yet completed in the areas relating to these products.  (Charts
and graphs with the info I wanted were missing, although there
was a "stub" pointing to them.)

Thoughts?  Thanks.

-Kirk  K4RO

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