[TowerTalk] Balun Recommendation

[Steve Hunt]

Jim,

I doubt it's material with as low a permeability as #61 or #67. If you 
look at the photos of the UnUn, you'll see it comprises 6 turns of coax 
on a core that is significantly smaller diameter than a size 240 
(probably a 140); that could never give the required winding impedances 
needed at the bottom end of the HF range for a 12.5/50 transformer. My 
guess is that it's #52 which I know this manufacturer uses widely - that 
would give him the required winding impedances with 6 turns.

73,
Steve G3TXQ

On 15/04/2012 01:08, Jim Brown wrote:
> Right.  Sorry, I slept through the details of your post. It's clearly
> acting as a classic magnetically coupled transformer, so  yes, I'd say
> it was a very good test, and that it  demonstrates very high
> efficiency.  From that, I'd guess it to be a material like Fair-Rite #61
> or #67.
>
>