[RFI] Ferrite Beads

[Tom Rauch]

 can see that the availability of cores is going to be a
problem.  You cannot buy what is not available.>>

I know DX Engineering is planning on stocking beads soon.
Not just now though.

Perhaps these companies have had the various mixes in the
past and simply do not produce them today.  It is the
initial permeability that I'm looking for?  It appears that
the high 'u' or high AL numbers will work the best.  Is this
true?>>>

You want the highest impedance at the operating frequency,
and hopefully it will be largely resistive. It's important
to consider frequency of measurement since permeability and
loss tangent does not remain constant at different
frequencies.

I've seen people overspec ui, and wind up with LESS
impedance at the working frequency than lower ui cores have.
Beverage transformers are one example that comes to mind.

73 Tom