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[TowerTalk] how deep a null do you need in a pattern..

To: "Towertalk" <towertalk@contesting.com>
Subject: [TowerTalk] how deep a null do you need in a pattern..
From: "Jim Lux" <jimlux@earthlink.net>
Date: Wed, 14 Jul 2004 22:21:29 -0700
List-post: <mailto:towertalk@contesting.com>
I'm doing some modeling, and an interesting question comes up, with respect
to nulling out interfering signals.

Say you have two stations, on the same frequency (or very close, so they
overlap), i.e. a pileup.  How much louder does one station need to be than
the other so that you can reliably copy it. 1 S unit (6 dB?)  1dB (that's
sort of the magnitude of a "Just Noticeable Difference")?

Different for voice or CW? (CW makes it a bit easier, because it's unlikely
that they're actually zero beat with each other, so there's a slight pitch
difference to help)

I realize that there's a lot more to it in practice (voice pitch, cadence,
slight differences in carrier frequency, etc. all help separate them
mentally).

What about if they're booming in at S9+?  S2-S3?  Down in the hiss?

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