[Milsurplus] what is it?

[Mike Hanz]

Not sure of the specific equipment, but this looks like an aircraft 
antenna tuner, missing the variable vacuum capacitor.  They're used with 
transmitters remotely mounted from the antenna using a long 50 ohm 
transmission line, and condition the antenna impedance to 50 ohms at any 
of the operating frequencies so that there are minimum losses in the 
coax.  The transmitter is pre-aligned to feed a 50 ohm resistive load, 
so tuning at that end is eliminated.  The concept works well with a ham 
antenna on the ground as well!

On 12/3/2011 10:19 PM, Paul Kraemer wrote:
>  From a pal of mine
> Very interesting rotary inductor driven by a servo
> Paul K0UYA
>
> https://picasaweb.google.com/davidjmessing/ServoRollerInductor?authuser=0&authkey=Gv1sRgCOSizuKckKuhSQ&feat=directlink