[Elecraft] WSJT-X and K3S Tx

[Richard Ferch]

1. The U7 is not on COM3. Sound cards do not use serial ports. Perhaps COM3
is a virtual COM port created by LP-Bridge, or perhaps COM3 is the K3S's
USB serial port, and COM7 is a virtual port created by LP-Bridge that you
connect other software to. You need to get this straight for other reasons,
but it has nothing to do with the audio issues with WSJT-X

2. Your default sound devices should be set to the motherboard sound card.
That is where Windows sounds are sent, YouTube audio and other media player
stuff goes, etc., and you don't want any of that stuff going to the sound
card(s) you use for radio, much less to the sound card you use with LP-PAN.

3. In WSJT-X, in the File > Settings menu under the Audio tab, set the
Input and Output sound cards to the ones you are using for sound card modes
- most likely the USB Audio CODEC in the K3S, unless you have chosen to
bypass it and use an external sound card plugged into the Line In jack on
the K3S, which disables the K3S's internal sound card. If you are using the
U7 with LP-PAN for panadapter software, it is *not* the sound card you are
using for sound card modes, and it should *not* be connected to the K3S's
Line In jack - it should be connected directly to the LP-PAN. In that case,
WSJT-X should be set to use the USB AUDIO CODEC and there should be nothing
connected to the K3S's Line In jack.

4. The ATU on the K3S is not triggered by a transmitted signal, whether
from WSJT-X or elsewhere. It is not auto-tune in that sense; it is
auto-tuning based on frequency memories, which is what the KAT500 calls MAN
mode. It will automatically switch to the last setting used on that band
segment with that antenna output (ANT1 or ANT2). Once you have tuned the
ATU once with your antenna for a particular frequency, that should be good
enough from then on. If your antenna's SWR changes dramatically because of
weather conditions, e.g. ice on the antenna, you tune the K3S's ATU using
the ATU TUNE button on the K3S. Therefore an extra 2-second tune signal
between band hops does not do anything useful, other than give you a
2-second advance notice of the SWR.

5. When the K3S's meter is in ALC mode, it does not show the transmitted
power. You have to put it into PWR mode with the METER button. The TUNE
button switches from ALC to PWR mode automatically, but transmitting
normally does not do this.

73,
Rich VE3KI