Xiegu X6100 Full-Band TX Setting: What It Does and How to Enable or Undo It

The Xiegu X6100 has a hidden setting that lets it transmit outside the amateur bands. It's just one line in a config file, and I get asked about it a lot. So here's what it does, what can go wrong, and how to back up first and undo it again. If you only use the amateur bands, you don't need it.

What the setting does

Out of the box, the X6100 only transmits on the amateur allocations. The radio runs Linux, and one setting in its config file, fullband-tx, controls that limit. Switch it on and the display shows a red F-TX indicator, and the radio will transmit outside the amateur bands. It doesn't make the radio any better at anything. It just removes the software restriction.

What can go wrong

  • Dirty output. The transmitter's filtering is designed for the amateur bands. Outside them you can get spurious emissions or harmonics that upset other services.
  • A poor match. An antenna cut for one band can give a high SWR on another, which is hard on the power amplifier.
  • Warranty and support. Changing the config may affect support from the maker or your dealer.
  • Accidents. It's easy to key up by mistake with the setting left on, for example by tuning off a band edge.

[ADD: your own notes from using it, such as which firmware version you tested on and any output or SWR measurements you took.]

Before you start

  1. Note your current firmware version.
  2. Back up the config file before you change anything (it's the first step below).
  3. Do your first test into a dummy load at low power, never into an antenna you're unsure about.

How to enable it

  1. Connect the radio's USB-C port to your PC.
  2. Install a terminal program such as Tera Term.
  3. Find the radio's COM port in Device Manager.
  4. Open Tera Term on that port. [ADD: the baud rate and other port settings you used.]
  5. Reboot the radio so the boot text appears in the terminal.
  6. Log in as root. The password is 123 on most firmware versions, and 1234 on some.
  7. Make a backup: cp /etc/xgradio/xgradio.conf /etc/xgradio/xgradio.conf.bak
  8. Open the file: nano /etc/xgradio/xgradio.conf
  9. Scroll down to the [mods] section and find the fullband-tx line.
  10. Change the value to enable, keeping the spelling of the file as you found it.
  11. Press Ctrl+S to save and Ctrl+X to exit, then restart the radio.
  12. The red F-TX indicator should now show on the display.

How to undo it

Go back in the same way and either restore your backup (cp /etc/xgradio/xgradio.conf.bak /etc/xgradio/xgradio.conf) or set fullband-tx back to what it was, then restart. The F-TX indicator should disappear. [ADD: whether a firmware update resets the setting, if you've tested it.]

Use it sensibly

  • Listen before you transmit, and never go near emergency, aviation or other safety frequencies.
  • Use the lowest power that does the job.
  • Switch the setting off again once you no longer need it.

Quick questions

Does it make the radio better on the amateur bands? No. It only removes the transmit restriction, so receive and performance on the amateur bands stay the same.

Do I need it as a UK amateur? No. All the UK amateur allocations are there on the radio as it ships.