[Elecraft] Elecraft] DATA-A tx freq offset with digital modes

[Edward R Cole]

Graham I do not know what program you are using to operate CW 
(perhaps FLdigi) but guessing this for HF.

On eme digital modes have become prevalent and using sw such as 
WSJT10 for that one can switch from say JT65 to CW by simple choice 
of mode on a drop down menu.  I have not operated CW-eme with this 
but many have been to accommodate some traditionalist who prefer to 
use CW.  The ability to switch modes in the sw without changing modes 
on the K3 (or K3s) is very convenient.  If one switches out of DATA-A 
the waterfall display stops receiving and one has no display of the 
received signal (an inconvenience).

So I just made a test using WSJT10 with my K3 connecting the 1.5mw 
XVT output to my frequency counter.
I simulated CW by pressing XMIT which displayed 28.124.998 (for dial = 28.125)
I have my CW offset to 600 Hz which I can hear with the monitor.

Then I tried running the CW mode on WSJT10 but the counter could not 
lock on such short duration tones.
So I set the sw up for test tones which typically are used for 
setting Tx audio levels in the K3.
Pressing the 1000-Hz tone gave the same RF frequency at the counter = 
28,124.998
That definitely is 1000-Hz vs 600-Hz but both mode output on the same 
carrier freq.

Switching to CW mode on the K3 while operating eme on digital would 
be cumbersome, so there may be times that using tone generated CW has 
advantages.  I guess its up to each operator to ensure clean 
operating settings and connections are existing if the do so.


73, Ed - KL7UW
http://www.kl7uw.com
     "Kits made by KL7UW"
Dubus Mag business:
     dubususa at gmail.com