[TowerTalk] Ferrites 31 vs. 77 material

[Jim Thomson]

Date: Sat, 2 Nov 2019 13:25:19 +0000 (UTC)
From: Roger Parsons <ve3zi at yahoo.com>
To: "Tower and HF Antenna Construction Topics."
<towertalk at contesting.com>, "jim at audiosystemsgroup.com"
<jim at audiosystemsgroup.com>
Subject: [TowerTalk] Ferrites 31 vs. 77 material

<Very funny.
<The posts from both N6RK and AB7E support my statement that variability in ferrite parameters has been known for a very long time. You're the one who asserted that it has just been discovered and that therefore Steve G3TXQ could not have known about it.

<73 RogerVE3ZI

##  I  believe it  was  N3RR  that  bought  700,   (seven  hundred)   type  31  cores  from  one  supplier,  all  from  the  same  lot number..2 years  ago.  He  used  a  simple  1 turn  link to test them..and then  graded them.  They were all  over the  map,  + and – 22%.   Thats a whopping  44%   spread.  No  2 ferrites  the  same!     ALL  made  in China......so what do  you expect ?  So  much  for  fairite moving  their  factory  to  China.   QC  down  the  tubes  ever  since.    

Jim   VE7RF