You won't believe what I found last night in the latest edition (5th edition)
of the ON4UN Low-Band DXing book related to my proposed common mode noise test.
Page 7-109 discusses using a battery powered receiver, and connecting the
receiver to the antenna using a "very short piece of coax" in or
I would also add that many times a SINGLE choke will not work and can
actually make things worse. This is because miscellaneous capacity to
ground, or actual grounding may be already minimizing the common mode to a
degree before you add the choke.
Adding the single choke may ISOLATE the miscellan
Jim K9YC said :
Second, a common mode choke does not in any way degrade
the signal nor the performance of the antenna.
but after more offline discussions with Jim about a posting by W8JI warning
that a improper value common mode choke can actually make things worse, Jim
clarified his sta
Don Kirk
The only way to eliminate Common mode noise is first of all understand the
basic concept what it is. Common mode noise is not a noise, it is actually a
signal generated by a current called common mode current because this
current flow in the outside of the feed lines. Not a big problem if
On 8/18/2011 8:22 AM, Don Kirk wrote:
> I hate to add extra components without verifying their need (also want to
> make sure I don't actually make things worse).
Two important points, Don. First, noise comes and goes, it isn't present
all the time. Second, a common mode choke does not in any w
I received numerous responses regarding my proposed common mode noise test,
and here is a summary of the responses.
1) The majority of respondents supported my proposed test.
2) There was really only one respondent that I thought provided a thumbs down
to my proposed test by saying "first te
A few weeks ago I installed 3 half size point fed pennants (each aimed
approximately 120° apart), and have been wondering if I need to install any
chokes and/or ground rod on the feedline near the feedpoint of this antenna
system to negate any common mode noise.
I then did a lot of research and
