Lyle,
I suggest adding a third variable capacitor (like in the Annecke boxes).
You can see this on L.B. Cybek (W4RNL) web site. Look for his article on
"Link Coupling" or "Link Coupled Matchboxes".
I will also send you the details (off reflector) in a PDF file.
In general, if you can't prune your antenna and feedline lengths to find a
match as is, then determine which position (40m or 20m) gives you the best
SWR on 30m. Then try adjusting the coil taps for that band. Try just a wee
bit more or less inductance and keep it symmetrical. You should be able to
find a tap which enables 30m to work along with either the modified 20m or
40m taps. The 3rd variable capacitor is the icing on the cake and enable
getting the SWR even lower on all bands.
BEFORE YOU TOUCH ANYTHING, don't forget to write down the exact settings of
the coil taps before the modification.
Good luck.
73
Rick
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Lyle Dunlap
Sent: Monday, March 27, 2006 5:25 AM
To: tentec@contesting.com
Subject: [TenTec] Johnson matchbox tuner
Someone came out with a fix for using a Johnson Match Box on 30M, here on
the reflector. Would that person or someone who remebers tell me how it was
done? Friend wants info. (forgive me for non TT subj matter)
Lyle W9FCX
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