That tuner is capable of all those combinations?
http://www.freepatentsonline.com/4763087.pdf
That is just a work of art. You can switch this to any combination or add
caps or inductance.
Looks to me the fixed capacitance is when your in a High voltage situation
gives you the isolation
you need when the variable cap starts arcing over. Then you run into the
cols heating up.
I moved my 100pF cap, that goes to ground, on the antenna side of the
series inductor, to the same input point at connection point of the tuner
and external network. So the output of the MFJ 989B
has a cap going to ground.
Arcing at 500 watts on 160M has stopped. I beefed up the coil and installed
an edge wound coil from a 1929 TBK transmitter. If my solder joints do not
hold up I will have to switch out the #12 copper connecting wire to copper
tubing.
Wish I had all those parts from the TBK, sold it all.
Alternating phase of feed line, isn't thats what they use to do on TV
antennas but they twisted it for the same reason? Hard to do with home
brew feed line. Must break up resonate lengths so not to be resonate on any
one frequency.
Ahhhh, the things we forget about that still work.
--
Jim K9TF
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Topband Reflector
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