Howdy all,
Just wanted to let everyone know how simple an MFJ-259 makes tuning
matching circuits. It's like child's play. Last night I did the input
circuits for my amp. I simulated the impedance of the 4-1000 by placing
appropriate resistors and caps to ground at the cathode pins of the tube
socket. Then I was able to tweak each input network for almost perfect
SWR. 20, 15 and 10 meters are less than 1.15:1 across their entire bands
(actually a good bit less). And 80 and 40 meters are less than 1.5:1
across their bands. I could play with 80 and 40 some more but it's
probably not worth it.
The nice thing about this was that I was able to tune up everything in
place. And it takes into account all of the other things like blocking
caps, filament choke, etc. It really works well. I wish I would have
had it in the past. It is worth the investment. Just wish mine was the
new "B" model. Oh well....the price was right!
It ends a lot of trial and error.
73,
Jon
KE9NA
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Jon Ogden
jono@enteract.com
www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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