Re: Variable coils

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From: lbrunson@rodgers.rain.com
Date: Fri Jun 24 1994 - 21:40:56 EDT


Mike Czuhajewski comments:
| Argh.....I would NOT recommend using an iron nail as the core for a
| variable coil unless you are working at DC or audio! If you are
| working with RF, use only core materials appropriate to the frequency.

I agree. I seem to remember that brass slugs instead of feromagnetic
material can also help to change the inductance of an inductor. Of
course, the inductance decreases instead of increasing with the insertion
of the slug. It does make a variable inductor, however.

Lowell Brunson (503) 681-0417
Rosenet: lbrunson@roland.co.jp
Internet: lbrunson@rodgers.rain.com (preferred)
           lowell@teleport.com
Packet Radio: KC7DX@K7IQI.OR.USA.NA


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