I completely agree with Tom. Carl! I'd leave it alone(for the reasons that
I stated previously)! I expect that you would lose more than you would gain
by adding an inductor!! "If it ain't broke don't "fix" it"!!
You might want to put some effort into a good terminated receiving loop!
73,
Charlie, K4OTV
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Tom W8JI
Sent: Saturday, February 22, 2014 9:09 AM
To: Carl Braun; '160'
Subject: Re: Topband: Shunt feeding the Skyneedle - new developments
Thanks for the tip. I may play with a bit of inductance just to see how the
system reacts. >>>
This is way more problematic than it needs to be.
First, no one even knows if the reactance is real or a false reading caused
by a bit error from calibration or noise.
Second, no one knows the sign of the reactance if it is there. It might be
already be inductive.
Third, if the capacitor is not maxed out or at minimum and still has range
left, which yours does, the capacitor will adjust out any reactance without
adding anything else.
There are certain bridge voltages that with even one or two bits error,
which is 2/256 bits or less than 1% error in voltages, where 10 ohms might
be calculated. The algoryth tries to take that error out by watching SWR
near bridge balance instead of bridge arm voltages, but I have no idea how
the unit is calibrated or if the antenna system has noise causing a bit
error.
All of this is pretty much meaningless. Even if it is a 1.3 :1 SWR, it is
not going to be a problem. Also, if the real part is near 40 ohms and you
have a high Q antenna system and losses, you might find lowest SWR is not
X=0 because of interactions between resistance and reactance as things are
tuned.
I would not even guess at a cure for something with a bunch of unknowns that
might not even be a problem. I think this is a bigger worry and more complex
than it should be.
73 Tom
_________________
Topband Reflector Archives - http://www.contesting.com/_topband
_________________
Topband Reflector Archives - http://www.contesting.com/_topband
|