Thread: Winding coils
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Old December 5th 03, 10:51 AM
Paul Burridge
 
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On 4 Dec 2003 17:30:27 -0800, Winfield Hill
wrote:

As John has said, that's a very low inductance that should not
present any problems at such a low power level. But perhaps for
a more detailed answer you can tell us the frequencies your coil
will experience. At high frequencies skin and proximity effects
dominate, and these can be evaluated with an Rac/Rdc ratio. If
a ferrite is used its high-frequency core loss can also be modeled
as an inductor resistance.


Thanks, Win! You're a diamond. John's formulae didn't appear on his
post for some reason, but you've given me the info I need to start
winding and be slap in the ball park right away. Great.
BTW, the factory inductors I have already are only about the size of
the newest half-watt resistors, so I was reluctant to chance it. I
know things keep getting smaller and somehow seem to defy the laws of
physics, but just call me old fashioned. :-)
Thanks again.

P.


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