It's STUB TIME again. For Field Day 96, our club is moving on up to 3A
based on the turn out in 1995. The logical way to divide the stations
is by using the DAY bands(10,15,20) and the NIGHT bands(80,40,20).
With that intro, I was looking at ways to reduce station interference.
Lets assume its night.... if I use ...
Station(80 meters), stub(shorted 80 quarter wave)
This will: Pass 80, Reject 40, Reject 20
Station(40 meters), stub(open 80 quarter wave)
This will: Pass 40, Reject 80, Pass 20*
Station(20 meters), stub(open 40 quarter wave)
This will: Pass 20, Reject 40
I would really like to ALSO reject 20 on the 40 meter station - 2nd harmonic
Now we get to the question...
Can I ALSO add an open 20 meter quarter wave stub to this station along with
the open 80 meter stub ? Can you use 2 stubs in line ? More than 2 ?
Is separation between them critical ? I would be using Tees in the line.
My gut feel says that it is OK since the stubs are acting as series or
parallel tunes circuits. This Ole Areo Engineer would like some
confirmation from someone in the know ... this electric stuff is magic.
More than one comment would increase the warm and fuzzy factor.
Thanks in advance.
73, Hank
K2UVG
Internet: jkahrs@delphi.com
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