[Amps] Permeability tuned tuning coils, with taps?

[Chris Wilson]

Thursday, January 16, 2014, 9:50:16 AM, you wrote:

> Somewhere in the seventies, in the ARRL handbook, there appeared a 6 meter
> amplifier tuned variometer style with a one turn shorted coil, rotating in
> the stationary tank coil. It wasn't very wideband as I can recall, but it
> worked.
> It seems to me, Chris, that you won't have any qualms about plagiarism: it
> was definitely more than 20 years back!
> Alex    4Z5KS 


I have an older ARRL Handbook showing a coil that is compressed and
allowed to re-expand via an internal threaded rod and two (Teflon?)
plates at either end. I have a Russian R-140 tetrode amp that uses
variometers, with complex auto control. Is "permeability tuning" the
correct description of a coil tuned with a none magnetic material
slug? Or is that getting pedantic?

Thanks for the replies.



-- 
Best regards,
 Chris                            mailto:chris at chriswilson.tv