Here's an idea that I wonder if anyone has ever tried. Being an impulse, the
lightning crash is essentially the same on all nearby frequencies. Would it be
possible to tune a second receiver to an empty frequency near 160 and subtract
that audio from the audio on the desired frequency, or phase the two so they
cancel?
Several problems come to mind with this scheme: (1) This might cancel the
lightning crashes and make it easier on the ears, but not clear how much of the
desired signal would be left; (2) properly phasing the two signals so the
lightning crashes in one cancel the crashes in the other, especially across a
whole width of the receiver passband; (3) receiver noise from the two receivers
would add together reducing overall sensitivity (might not be an issue on 160,
since there's always some QRM/QRN from somewhere at those frequencies).
Any thoughts?
Art Delibert, KB3FJO
> From: wb6tza@socal.rr.com
> To: Topband@contesting.com
> Date: Mon, 26 Mar 2012 19:57:32 -0700
> Subject: Topband: how to hear through static crashes?
>
> Maybe this is a good time to share the techniques we individually find
> successful for
> hearing through the giant sparks.
>
> Directional receive antennas, obviously,
>
> Receiver AGC?
> IF bandwidth?
> IF and RF gain distribution? (includes antenna preamps)
> what classes of digital processing do better?
> what's the best way to keep the receiver processing from ringing and
> increasing the
> effective duration of the crash?
> noise blanker performance?
> post receiver audio processing?
> can you let the IF strip "clip" in a modern receiver and be an effective
> "peak limiter"
> without serious ringing?
>
> What do YOU do? and with which receiver?
>
> some shared experience might remind all of us of things to try to hear when
> the big sparks
> are flying
>
> Robin, WA6CDR
>
>
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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