Getting a Xiegu G90 on FT8 is not particularly difficult, other than there is just a lot of it. The radio needs the right mode and audio settings, the computer needs the correct sound devices, CAT control needs to work, your clock needs to be accurate, and WSJT-X needs to know how everything is connected.

Miss one setting and you can end up receiving but not transmitting, transmitting with no power, seeing no decodes, or wondering why nobody answers you.

I walk through the entire setup from an untouched radio to an actual FT8 contact in the video below. If you're setting up a G90 for the first time, I recommend watching the video once before changing anything, then coming back to this page and using the cheat sheet while you configure your station.

Watch the complete Xiegu G90 FT8 setup video

This guide uses a Xiegu G90, TOADs DI8 digital interface and WSJT-X 3.x, but most of the computer and WSJT-X information applies to almost any radio.

What You Need

The basic signal chain is:

Xiegu G90 → digital audio interface → computer

You will also need a separate CAT connection between the G90 and computer.

For the setup shown in the video I used:

• Xiegu G90

• Antenna appropriate for the band

• G90 8-pin accessory cable

• TOADs Digital Interface with the DI8/Xiegu connection

• USB cable for the digital audio interface

• Xiegu CAT/serial cable

• Windows, macOS or Linux computer

• WSJT-X

A Raspberry Pi works. A mini PC works. A Mac works. An old laptop works. FT8 does not require a fire-breathing gaming computer.

The digital interface handles audio into the radio, audio out of the radio, PTT and ground through the G90 accessory connector. The separate CAT cable lets WSJT-X control things such as PTT and frequency.

Xiegu G90 FT8 Cheat Sheet

These are the settings I use as a starting point.

Download and Print Your Cheat Sheet Here 

Important: Do not treat the RF Gain number or audio levels as magic numbers. They are starting points. Every antenna, computer, sound device and local noise environment is different. The meters in WSJT-X are what ultimately tell you when you have things adjusted correctly.

1. Connect Everything

On the rear of the G90 is the 8-pin accessory connector. Connect that to your digital interface. With the TOADs DI8, that gives the computer access to the G90's transmit and receive audio path.

Connect the USB side of the digital interface to the computer.

Next connect the Xiegu CAT cable between the computer and the G90's serial/CAT connection. On the radio, this is not the CW key jack, firmware-update connection, IQ connection or headphone jack. In the video I show exactly which side-panel connection to use - the lower one.

Finally, connect your antenna.

One G90 CAT-control gotcha

On the G90 firmware demonstrated in the video, I encountered an intermittent CAT-control problem that could cause the radio to behave strangely, including very low transmit power or trouble powering up normally.

If your G90 begins acting bizarrely, disconnect the CAT cable before power-cycling the radio and test it again.

That one is worth remembering because it can send you chasing completely unrelated audio and antenna problems.

2. Set Up the G90

Before touching WSJT-X, get the radio into a predictable state.

Turn PRE, ATT, COMP, NB and AGC OFF.

For digital modes, I want as little radio-side processing as possible. Let WSJT-X and the computer work with the received audio instead of having the radio constantly changing its level.

Set the radio to U-D, meaning upper-sideband digital.

This one is critical.

FT8 uses upper sideband, including on bands where you might ordinarily expect another voice sideband convention. On newer G90 firmware, the digital mode is labeled U-D. Older firmware may have displayed this differently.

If the radio changes from U-D to regular USB when WSJT-X keys it, you can end up with little or no transmit output through the accessory audio path.

Filters

Open the filter as wide as practical, approximately 3000 Hz. WSJT-X is listening to an entire audio passband containing many simultaneous FT8 signals. A narrow voice-style filter simply throws away signals the computer could otherwise decode.

AUX levels

In the deeper G90 menu I use:

• AUX IN: 8

• AUX OUT: 7

Those give us known starting points before doing the fine adjustment at the digital interface and computer.  Long-Press the function button to access the deeper menu.

RF Gain

Long-press the AGC control to reach RF Gain.

I generally begin around 50%, but don't blindly copy that number. Watch the receive-level indication while actual FT8 signals are present.

You want useful signal without continuously driving the receive audio into clipping.

Power

The G90 can produce 20 watts, but FT8 is a demanding duty cycle. The transmitter will run approximately 15 seconds continuously, rest for 15 seconds, and repeat that cycle over and over.

I normally start around 5 watts, check the radio's temperature, and work upward if necessary. I used about 10 watts during the video.

Mechanical empathy applies here. The goal is making contacts, not discovering the melting point of a G90.

3. Install and Configure WSJT-X

Install the current stable version of WSJT-X for your operating system.

The configuration is essentially the same on Windows, macOS and Linux.

Linux users have one extra chore: your user account needs permission to access the serial port. On the Linux Mint XFCE system in the video, I added my user to the dialout group and then logged out and back in so the new group membership would take effect.

Now we launch WSJT-X for the first time and open:

File → Settings

General

Enter:

• My Call: your callsign

• My Grid: preferably your six-character Maidenhead grid

I also enable useful options including:

• Blank line between decodes

• Double-click on call sets TX enable

• Disable TX after sending 73

• Calling CQ forces Call 1st

I use a 6-minute TX watchdog as well. If I accidentally sit there calling CQ forever, WSJT-X eventually stops transmitting and gives the radio a break.

Ham Radio is a hobby all about experimentation!  Hover over unknown options, read tool tips, turn them on and try them out.

4. Configure the Audio Devices

Under the Audio tab, select the USB audio interface for both input and output.

The TOADs DI uses a C-Media CM108-family USB sound device, so it may appear as something similar to:

C-Media Electronics
or
USB Audio Device

Do not accidentally select your laptop speakers as output and its microphone as input.

Technically, FT8 can work acoustically with a computer microphone listening to a radio speaker, but that is very much the “we've been stranded on a desert island with one USB cable” solution.

Use the digital interface.

5. Configure CAT Control

On the Radio tab:

Rig: Xiegu G90
Baud: 19200
PTT Method: CAT
Mode: None

For the serial port:

• Linux: usually /dev/ttyUSB0

• macOS: normally the appropriate /dev/cu... device

• Windows: the appropriate COM port

If you have several USB serial devices, the number can change. If CAT suddenly stops working after rearranging cables, come back here first.

Click Test CAT.

A green result is good, but the more important test is Test PTT. Click it and confirm that the G90 actually switches into transmit.

Split: None, Rig or Fake It?

WSJT-X can move the radio's transmit frequency so your transmitted audio stays in a favorable part of the radio's passband.

Rig uses the radio's VFO A/VFO B split system.

Fake It momentarily moves the operating frequency using CAT.

I generally prefer Fake It because I've encountered situations where VFO A was correctly configured for U-D while VFO B was sitting in ordinary USB. The radio switched VFOs and suddenly the digital audio path wasn't behaving correctly.

If you want the simplest possible troubleshooting configuration, None also works. You simply need to choose your transmit audio frequency intelligently.

Whichever method you use, make sure the G90's own SPL function has not accidentally been left on. In the video, an apparently impossible WSJT-X frequency/mode change turned out to be the radio switching to VFO B because SPL was enabled.

6. Set the Receive Audio Level

Watch the receive-level meter in WSJT-X while signals are present.

WSJT-X recommends roughly 30 dB with noise only, but actual FT8 signals will drive the meter higher. During active signals I tend to see mine around the neighborhood of 70.

The important part is the color:

Green is good. Red means clipping.

Use the G90's RF Gain as the coarse adjustment, then use the receive trim control on the TOADs DI as your fine adjustment.

Those trim pots are multi-turn controls. Don't expect a quarter-turn to cover the entire adjustment range.

7. Set the Transmit Audio

At the computer level, make sure the USB audio interface is selected for output.

In the video I initially set the operating-system output level to 100% so I had a known reference point.

Then press Tune in WSJT-X.

The G90 should key and produce RF power.

Use the transmit trim adjustment on the TOADs interface for fine control. Once everything is calibrated, the computer's output level can provide a convenient coarse adjustment.

Do not assume that turning every audio control to maximum produces a better signal. You want enough audio to produce the desired RF output without unnecessarily overdriving the radio. Extra loud audio just gets clipped by the ALC circuit.

8. Make Sure Your Clock Is Correct

FT8 is synchronized to time.

Look at the DT column in WSJT-X. That's delta time, showing how far another station's timing appears to be from yours.

Modern operating systems normally synchronize their clocks automatically, but verify it. In the video I use time.is to check the computer against accurate Internet time.

If WSJT-X shows signals on the waterfall but you are getting very few or no decodes, check the clock before dismantling the station.

9. Pick a Clear Transmit Frequency

The frequency numbers in the WSJT-X waterfall are audio frequencies inside the radio's passband, not the dial frequency displayed on the G90.

For example, the standard 20-meter FT8 dial frequency is:

14.074 MHz

Within that approximately 3 kHz passband are many individual FT8 signals.

Look for a clear area on the waterfall. I prefer a location that appears clear during both the even and odd 15-second periods.

Right-click the waterfall to place your transmit marker and enable:

Hold TX Frequency

That lets you receive a station elsewhere in the passband without jumping your transmit signal onto somebody else's existing QSO.  Make sure this is turned on!

10. Call CQ

To call CQ, select the standard TX 6 / CQ message and click:

Enable TX

The button turns red and WSJT-X begins transmitting on the appropriate 15-second cycle.

When someone responds, WSJT-X works through the normal exchange:

Call/Grid → Signal Report → Roger/Report → RRR/RR73 → 73

When the exchange completes, the logging window appears (if configured).

I like to retain my power level and put useful station information in the comments, particularly because I change equipment frequently:

• Radio

• Antenna

• Digital interface

• Power

That gives future-me some context when looking through old contacts.

Nobody Answering? Check PSK Reporter

No response does not necessarily mean your station isn't working.

Go to PSKReporter.info, search for signals sent by your callsign, select FT8, and narrow the time period to something useful such as the last 15 minutes.

If receiving stations hundreds or thousands of miles away are reporting your transmission, congratulations: your station works.

Nobody happened to answer.

That's an important distinction.

I also enable PSK Reporter Spotting inside WSJT-X so the signals I receive contribute to the same network.

G90 FT8 Troubleshooting

If things aren't working, work through the chain instead of randomly changing settings.

Receiving signals but getting no decodes:
Check the computer clock, audio input device and receive audio level.

WSJT-X shows no receive audio:
Verify that the USB audio interface, not the computer microphone, is selected as the input. (U-D)

Radio keys but produces zero or very little RF:
Make sure the G90 is still in U-D, not ordinary USB. Verify the computer audio output device and output level.

CAT doesn't work:
Check the serial-port selection, 19200 baud and USB connection. Linux users should verify membership in the dialout group.

Radio suddenly changes frequency or mode when transmitting:
Check that the G90's own SPL/Split function is OFF. Also inspect your WSJT-X Split Operation setting.  In Split or Fake It mode, frequency changes are expected, mode changes are not.

G90 behaves strangely after using CAT:
Try shutting the radio down, disconnecting the CAT cable, and power-cycling it.

Receive meter is constantly red:
Reduce the digital interface RX level and/or G90 RF Gain.

Everything appears to work but nobody answers:
Check PSK Reporter before changing anything.

The Most Important FT8 Setup Advice

Don't change six things at once.

Get receive working first. Make sure you see signals. Get your audio level out of clipping. Confirm that you're decoding signals. Verify the clock.

Then test CAT.

Then test PTT.

Then use Tune and verify RF output.

Then transmit.

FT8 becomes much easier to troubleshoot when you think of it as several small systems connected together instead of one enormous collection of mysterious settings.

If you want to see every menu, connection and adjustment demonstrated on the actual G90, watch the complete setup video. I take the station from the physical wiring through WSJT-X configuration, audio adjustment, CAT control, PSK Reporter and finally an actual FT8 contact.

Watch: Xiegu G90 FT8 Complete Setup Guide
https://youtu.be/OVEf7nWYkpo

And keep the cheat sheet above handy. Once the station is configured correctly, you can use the last column to write down your preferred settings for when you're not working FT8 for easy switch-back.

Enjoy Your Radio!