John McFarlane

Seattle, WA

WSJT-X with FT-991A on Linux

Posted on
#ham #FT-991A #WSJT-X #digital

Installation

sudo dnf install wsjtx

Radio settings

Menu Setting Value
029 232C RATE 34000bps
031 CAT RATE 34000
062 DATA MODE OTHERS
064 OTHER DISP (SSB) 1500Hz
065 OTHER SHIFT (SSB) 1500Hz
070 DATA IN SELECT REAR

DT GAIN

The goal is to use the highest value, but with no visible ALC

  1. Set the radio METER to ALC
  2. Use the TONE button in WSJT-X to transmit
  3. Raise the DT GAIN until you see ALC
  4. Then dial it back down until the ALC is no longer visible
  5. Stop transmitting (ie: click the TONE button again)

Lots of people will say to keep DT GAIN at or below 10. I tried this, and virtually no one ever heard my signals. Using higher values made a enormous difference in my setup. Note as you approach 75W you will probably see your ALC start to increase, at which point you’ll need to reduce your DT GAIN to prevent visible ALC.

MONI

The radio monitor can be used to verify that the computer is able to transmit using the radio’s USB sound card. This is particularly useful when using the software TONE button. Set the MONI to 50 and listen to the tone to ensure it’s clear and free from clipping or distortion. Just remember to turn it back off when you’re done testing or it’ll drive you nuts.

RF POWER

The goal is to use the lowest power possible.

  1. Start with 5W
  2. Work your way up as needed

Software settings

Pwr

The volume slider on the far right side. I set this to half way.

Pwr

Rig control

I use Rig which causes the software to put the radio into split VFO mode so it listens on one frequency and transmits on another.

General

general settings

Radio

radio settings

Audio

audio settings

General tips

  • Be careful with USB hubs. I was using one with my Lenovo T490s and was all the sudden not able to get any audio from the radio. Eventually I realized I had moved my office around and plugged the radio in via a hub. Plugging it directly into the radio fixed it right up. I presume my hub is rubbish.
  • Note the Rig Mode used by the software. I made contacts with it set to None, but I had way better luck after setting it to Rig, though that also coincided with using a much higher DT GAIN. Maybe I should test to isolate the two.
  • Try to line up your transmit frequency to be offset from the receive (red and green). I can’t say I’ve noticed a big difference, but it’s considered a polite practice from what I gather.

References (random order)