[RFI] RFI LG Refrig Corcom filter and #31 core

[Jim Brown]

I used to think that, but I was mistaken. #43 is NiZn, #31 is a very 
special MnZn material. NiZn materials are relatively high-Q as compared 
to #31, which is a very special MnZn formulation.

Once we realize that 1) #43 is designed for mid-to-high VHF to get 
products through EMC testing; 2) Rs in a choke is far superior to Zmag, 
3) much higher Rs values can be obtained by winding turns to move the 
VHF resonance down to HF, and that the higher Q of the NiZn material 
exacerbates tolerance issues, #31 is actually moderately superior to #43.

73, Jim K9YC

On 10/13/2021 11:43 AM, David Eckhardt wrote:
> If it ever becomes a problem, again, 43 material would better serve
> 10-meters than 31 material.  The difference is small, but if needed, it
> could be useful.