[Amps] slug tuned variable inductors

[Chris Trask]

    Not around any appreciable power, no.  The losses in the ferrite may
cause it to heat up excessively.  Even more so with powdered iron.

Chris

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----- Original Message -----
From: "Joe Brown" <joe.brown at gordmans.com>
To: <amps at contesting.com>
Sent: Wednesday, February 16, 2005 2:14 PM
Subject: [Amps] slug tuned variable inductors


> Is it possible to use slug tuned coils with any reasonable power? I am
thinking of moving a ferrite slug in and out of a coil to change the
inductance, but don't know if it would be too lossy at real power? Is there
a type of ferrite that could be used for this at HF? Or is this just a goofy
idea. I want to get rid of the roller inductor in my homebrew antenna tuner.
>
> I read an article in an old Ham Radio magazine about a tank circuit for a
commercial 5KW amp, and they lowered the inductance by moving a shorted turn
( a piece of copper pipe) in and out of the tank coil. Wondering if can do
the same thing with ferrite.
>
> 73, Joe W0DB
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