[Elecraft] Keying CW in SSB Mode

[Bob McGraw K4TAX]

Ted, Fred et al;

As a rule using the SSB mode to send CW is very risky at best. Any hum 
or distortion, meaning the smallest amount,  on the CW generated audio 
signal will produce harmonics of the fundamental audio tone .   These 
will  pass through the SSB generator and sideband filter and thus be 
transmitted.  {i.e. - 700, 1400, 2100, 2800 Hz}   Probably at levels in 
excess of the FCC regulation on signal purity.   Not to mention 
upsetting your band neighbors around your frequency.

The earlier references I made to using FLDIGI and a Signalink USB 
interface, FLDIGI does generate CW audio.  It is this audio signal 
which  activates the relay in the Signalink USB, thus it is a relay 
which is performing the function of keying the radio in CW mode.  No 
different than a straight key.  In this case, the radio MUST be in the 
CW mode, the Signalink USB Delay set fully counter clockwise to 
minimum.  Even then, the speed of the associated circuits and the relay 
close and open time will limit CW speed to less than 20 WPM or so.

Other software applications may behave differently when connected direct 
to the radio or via an interface device.   No one rule stands for all 
configurations.

73

Bob, K4TAX



On 7/3/2017 3:00 PM, Fred Moore wrote:
> Ted, it's not a great strategy any time, and yes most likely that is
> what was going on.  You should see their signal when they have RF on the
> audio or a hum.  Not exactly meets the FCC requirements.  If you are
> listening with a wide filter some times you even get to hear their
> Microsoft Windows generated tones if they forget to turn them off.
>
> Let the flood gates start with all of the "you can't tell the difference
> so it's ok"  But I can and have seen it many times with bad signals..
>
> It's not CW keying, its USB or LSB keying with a single tone.   It makes
> me crazy when someone calls it CW keying, no way it is
>
> Fred
>
> Fred Moore
> email: fred at fmeco.com
>         wd8kni at gmail.com
>