[RFI] Is a Micrometals T44-52 a useful Ham toroid?
tcgroat at mesanetworks.net
Sat Jul 7 17:33:40 EDT 2007
Technical information can be found at
<http://www.micrometals.com/materials_index.html>. In general, #52 is a
"power conversion" material: mu = 75, but poor Q at RF. The low
permeability allows it to handle considerable DC current without
saturating. That makes it useful for differential-mode power line filters
and the like. Mix #52 is often used for output filters of switch-mode power
However, like all iron powder cores #52 won't perform as well as ferrite
for common-mode suppression because it has much lower permeability. It
won't easily replace beads and snap-on cores when you need to suppress
common-mode currents, because it takes many turns to equal the impedance of
one turn in a ferrite core.
The low Q of #52 mix makes it undesirable for transmitter output filters,
tuned circuits, and other applications where RF loss would be a problem.
For high Q circuits, choose a low-loss mix that's made for RF (such as #2,
#6, or #17).
I hope this helps!
kd4e <kd4e at verizon.net>:
>I have come upon a source of toroids 5/8" x 5/8" x 3/8"
>They contain a 7/16" diameter powdered iron core
>(Micrometals T44-52) wound with approximately 7 turns
>of copper wire for a nominal inductance of 1.7 uH at
>0 DC current.
>They are marked with the part numbers; HM00-98502, BI 9839 M
>Would these be useful as-is or rewound for dealing with
>RF problems in the Shack or elsewhere?
>Does the size or type indicate power handling capacity
>and frequency relevance?
More information about the RFI