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[TowerTalk] Johnson Matchbox Tapped Input Coil

To: towertalk <towertalk@contesting.com>
Subject: [TowerTalk] Johnson Matchbox Tapped Input Coil
From: Tom Hellem <tom.hellem@gmail.com>
Date: Tue, 15 Mar 2022 12:41:17 -0600
List-post: <mailto:towertalk@contesting.com>
HI Tom, K0SN,
I have tapped the input coil on a Matchbox. I have taps on 5 turns as I
remember. This greatly expanded the matching range. As I remember I used
270 pF air variable in the low side of the link coil. I used a ceramic
switch from an old BC-610 tuning draw. The switch size in excess of that is
needed but was available.

I did this about 25 years back and it has worked very well with no issues.

The fun part is getting the switch and variable cap control shafts being
available to the operator and actually putting the coil taps in place. I
had to make a hinged plate access panel into the top of the tuner to allow
proper assembly of the modifications.

In my opinion it is worth the effort.

Tom, if you could post this it would be nice. It seems that Tower Talk does
not allow me to post.
Russ, NM3DX
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