Hi Matt,
There are three ways to change that tuning range. You
can increase the inductance of the stock 4.7uH choke by
a few turns around it. I wote a post about that a few weeks
back. Try three turns. If your tuning range goes down, you
have wound it the wrong way. When you get the number of
turns which make your rig tune the way you want, put some
glue on the choke.
A second way is to put a variable cap in series with the
higher choke value you now have installed. That will cancel
some of the inductance, and you can set the bottom end
wherever you want. This mod also reduces your tuning
range by a small amount.
The third way is to put a second variable pot in series with
the ground end of your tuning pot. This will raise the lowest
voltage that can be applied to the tuning diode, and again
reduces your total range, but again will allow you to easily set
the low end of your range.
72/73 Dan Winkler N7IVR Seattle WA
..
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