Indeed there is much good software out there that you can use to examine
signals. I use this stuff in my radio telescope work. For frequency domain
signals I like SpectraPlus. I use skypipe software for my time domain
signals.
And finally, I have my techtronics scope with a little bit of "antenna"
hooked to
one input to sample the signal right off the air. All of the above are
recommended to the serious obsessive compulsive Ham...like me :))
73 de Gary, AA2IZ
----- Original Message -----
From: "Jim Reid" <jimr.reid@verizon.net>
To: "Alderman, Chester" <CAlderma@ora.fda.gov>; "'Mike Hyder -N4NT-'"
<N4NT@charter.net>; <AC5E@aol.com>; <w8au@sssnet.com>
Cc: <tentec@contesting.com>
Sent: Thursday, November 28, 2002 6:23 PM
Subject: [TenTec] Key Clicks Made Visible!
> Happy Thanksgiving Weekend!
>
> Have discovered a program, using your mike, computer
> sound card with the mike plugged in, and a free (for 15 days
> use) downloadable program from Germany.
>
> The program uses fast Fourier Transforms to show the audio
> spectrum plus it shows the individual dits and dahs of a CW
> signal. It is called "MRP-40", very interesting. To check it out,
> go to:
>
> http://www.polar-electric.com/Morse/MRP40-EN/index.html
>
> Note the sample screen shot showing a string of dits and dahs.
> When key clicks (artifacts) are present, there will be vertical
> lines going, maybe, both above and below the initial dit or
> dah; also, sometimes at the trailing edge of the CW element.
> These are higher pitch artifacts, if they go up, and lower clicks
> if the tails go down.
>
> Good, clean, click free CW elements have NO tails, either
> going up or down. Try it and see for yourselves -- clicks
> exist on many signals, and also, many signals are very
> clean.
>
> Click on GoMax, and the program selects the strongest
> CW signal of the display to track; or just click the mouse
> on a string of dits/dahs of interest, program again immediately
> will track it.
>
> The side tone pitch to which the FFT filter is tuned appears
> in RED in the small window at the right of the MRP display.
> You can fool around with the FFT settings and the speed of
> the program.
>
> I now know that I am really hearing key clicks, hi. Listen
> to the signals which show the "artifacts"; you can actually
> hear the delta between clean signals and those not.
>
> Just monitored K7UD (14031) who was running an Omni V at 70
> watts at 37 wpm -- no clicks!
>
> 73, Jim KH7M
>
>
>
>
>
>
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