How about a normal L-type network? Connect one side to the
balanced
line, and the other side via a current balun to the 50
coax. The tuner
is 'RF-floating'. (You can run the coax through a toroid
or use two
seperate wires to make the current balun.)
Arie,
Respectfully that does not work at all for common mode
problems, which are the only problems that are difficult to
solve anyway. It is quite evident why this will not work if
you simply draw it out on paper and plot the voltages.
The problem is one terminal of the balun is connected
directly to the balanced feedline. The flux levels in the
balun core, the balun core losses, the amount of unbalance
are all unaffected by the balun move because one terminal of
the balanced line is always connected to the balun.
I forgot that I actually put measurements of this, along
with spice models, on my website. You can see why it doesn't
work at this link:
http://www.w8ji.com/tuner_baluns.htm
A balanced network will eliminate the need for a balun on
the tuner output, but a truly balanced network works nearly
the same with or without any balun!!! The ONLY time moving
the balun to the input could help the balun core stay cool
is when you don't even need the balun in the system.
Ironic isn't it? It only significantly could help when it
isn't needed.
73 Tom
_______________________________________________
Elecraft mailing list
Post to: [email protected]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
