Wide CW signals

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I'm watching a pileup (I can't hear the DX) on 40m.  Although the peak signal levels are similar, some signals are considerably wider and "fuzzier" on the waterfall than others. Is this a case of poor adjustment or are these operators deliberately doing something to make their signals stand out?
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Mark Erbaugh

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Posted 3 years ago

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Steve - N5AC, VP Engineering

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The rise time of the CW signal directly affects the bandwidth.  W8JI has captured a number of good papers from various authors on his website concerning this.  Look here:

http://www.w8ji.com/keyclicks.htm
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Mark Erbaugh

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Steve,

Thanks for the reply. The link was helpful. Is there an explanation somewhere of the CW keying envelope on the 6000 series?

73,
Mark
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Simon Lewis

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Mark,

or a combination :)

Also don't forgot you are also 'seeing' the effect of propagation on signals.

It's quite possible some signals get smeared across the path.

Quite often I see on 17/15/12 etc multipath, echos and smearing of signals.

Of course not all the time.

Some I see as overdriven amps, key clicks and general mis tuning

I can hear that effect before on the TS590's .. now I can actually 'see' it

If you want to see the effect look at a dxpedition running RTTY

most signals you will see are clean but occasionally you can hear an overdriven grotty signal and by the heck you can see it on the panadapter!

Here's VK2CR using a commercial amp .. .over driven over processed audio

Wide as a barn door.. 15 KHz wide ... he sounds 'loud' but distorted

a similar VK left is loud as well .. but not splattering 

The ghosting on the left behind the SSB signal is radar!

So yes .. you can see multiple effects

Cool or what!

I'll never buy radio again that won't display this level of detail ..

:)

Cheers

Simon ZL4PLM 

mmercial amp