[Elecraft] [KX3] DATA A Digital Modes

[Joel Black]

Need a little help here - or at least someone to tell me if this is normal for the conditions or not.

I usually use my K3 connected to a Focusrite 2i2 external sound card for digital modes. I use a Mac - OS X 10.11.3. It works very well and I like it (the 2i2) even better than the previous USB sound card I used.

Yesterday, I got a wild hair and decided to test the KX3 with the 2i2 using WSJT-X for JT65. I connected the KX3 mic to line out and the speakers to line in on the 2i2. The first thing I noticed was the audio seems really low when trying to listen through the sound card to receive audio. Now, this may just be where I’m trying to monitor the receive audio - from the monitor jack on the front. I also noticed a large spike with a dip and then another smaller spike before leveling out on the waterfall display of WSJT-X. I have *no* audio interface going into the sound card from the KX3 so I’m wondering if this is a ground loop issue. I do not have this issue with my K3 and I have no way to connect a ground to my computer other than to use a self-tapping screw and drill a hole in the case which I am not going to do - forget it. Unless you have an iMac, you won’t understand. I switched between LINE and INSTRUMENT on the inputs of the 2i2 but didn’t get much of a change. I did *not* try turning on the 48V phantom power on the inputs. From all I can research and look at on the case, there is no “ground-lift” switch on the 2i2.

On the transmit side, I never could set the ALC to four bars with the fifth just flickering *and* keep output at 5 W. The power would dip down to about 3 W and then go back up to 5W. In addition, there seemed to be a little ringing when transmitting.

Now the KX3 is not my main radio, my K3 is. This is not an issue with the K3, but I’d like to see this work with the KX3. I know it works because others have made the KX3 work on JT65 with WSJT-X. Is there anything else I should try before building an audio isolation circuit? Some setting I’m missing? Something I haven’t done correctly?

Thanks for the help.

73,
Joel - W4JBB