Re: K3 performance - soft keying and linear key output

Posted by Bill W4ZV on Dec 29, 2007; 4:23pm
URL: http://elecraft.85.s1.nabble.com/K3-performance-soft-keying-and-linear-key-output-tp457679p457680.html

<quote author="Dave G4AON">

I've just done some measurements with my K3... CW waveform rise and fall
times are both 5 mS (and doesn't alter when the speed is changed with
the internal keyer), which some would consider a bit soft - although my
measured bandwidth for 20 wpm keying at 100 Watts of RF is +/- 500 Hz at
70 dB below peak output, which is probably as clean as it gets.

        Elecraft has chosen not to allow users to adjust Rise/Fall times although
I suspect they remain open to input on the issue.  This is not necessarily
a bad thing!  The IC-7800, Orion and FT-2000 all allow adjustment, but
they ALL set default times that are guaranteed to generate key clicks.

        The problem seems to be that the stated Rise/Fall times in their
menus are actually about twice actual.  Thus setting 5 ms in will generate
measured Rise/Fall times of ~3 ms and hence key clicks.  To tame Orion
you must set 7-8 ms which generates an actual waveform with Rise/Fall
in the area of 4 ms.

        Kudos to Elecraft for NOT shipping the K3 in a default state that is
guaranteed to cause key clicks!

                                                     73,  Bill  W4ZV