New Firmware for X6100

There’s a new person building onto Oleg’s R1CBU firmware. He first made a patch TGZ available, and then an entire image.

He has a repo for this work, and it includes some build instructions which reference the buildroot and submodules. I think I’m close to being able to build it, but I’m seeing some errors trying to find the xkbcommon headers.

I did patch his source with my DB changes. I built the DB: sqlite3 params.db < params.sql, mounted the DATA partition, and copied my custom params.db to it.

It’s looking nice so far. I can use flrig and have wsjtx and fldigi both talk to it simultaneously. That’s the main improvement in my mind, but it includes some other fixes:

  • volume encoder can be spun quickly now
  • smoothing of the TX/SWR graphs
  • finer detail in the waterfall

Adjusting Bands on R1CBU

I updated the bands on my X6100 running R1CBU to follow the US band plan/privileges:

  • Clone source:
  • Update sql/bands_ham.csv to break bands by plan and privileges for US
  • Update sql/params.sql to not import band_params.csv, but to instead build it from the bands table
  • Rebuild the db: sqlite3 params.db < params.sql
  • Copy the new params.db to the DATA partition of the SD card

Rebuilding the database loses all your settings on the radio, so you have to put those back, but I can now see where the general privileges start and end on each band.

[Read More]
r1cbu  x6100  bands 

R1CBU 0.20.1

I updated my X6100 to R1CBU 0.20.1. Oleg provided a tgz with only the updated files, so I dropped the file into /DATA partition, started up the radio, and it unpacked the update. The tgz contained the x6100_ui binary and params.db.

This can be an interesting way to make my own updates without needing to know how to rebuild the entire image. I see the changes applied to his x6100_gui github repo, so I know that’s a good base for making future changes.

Learning to do make updates is interesting, because the original maintainer, Oleg, is likely done updating this firmware in favor of building his own radio in the image of the X6100. He’s frustrated trying to get help and documentation from Xiegu. I run the R1CBU firmware full-time.

r1cbu  x6100 

R1CBU 0.20.0

A new R1CBU firmware is available for the X6100.

I wrote the image to the micro SD card:

$ sudo dd if=x6100_r1cbu_v0.20.0_sdcard.img bs=1M of=/dev/sdb status=progress

It’s working fine. Auto levels for waterfall and spectrum seems useful, but it still shows the min/max level settings that do nothing while in auto. I had to set up all preferences again, since it comes with a new database on the image.

x6100  r1cbu 

RTTY Round-Up

I participated in the RTTY Round-Up.

Trouble with fldigi/R1CBU

I screwed around lots trying to get fldigi talking to the radio. R1CBU software works great with wsjt-x, but fldigi and flrig completely failed to connect. It wouldn’t key the radio. Switching back to stock software on the radio worked fine with flrig, but where’s the fun in that.

For flrig, I could tell it that it was an older version of the radio (X5105?), and it would key and set frequency, but flrig wouldn’t read back the frequency when updated at the radio.

I ultimately got fldigi talking to R1CBU by using flcat with an xml file for G106.

Then I could “tune” power output following instructions in fldigi manual.


I started making some contacts on 10M and 15M. It’s much more like voice contacts: yelling back and forth on the same channel. I’m using macros and sticking to those for the contest. They’re on the 3rd page of macros in fldigi.

I’ve made at least a few contacts, so I’ll submit them to the contest

rtty  hf  arrl  contest  r1cbu  flrig  fldigi 

R1CBU on X6100

I’ve loaded the R1CBU UI on the X6100. Reading the manual exposes all sorts of great features and conveniences:


  • Large waterfall
  • Lots of options on MFK and VOL knobs, and it’s customizable
  • SWR scan is very fast
  • CW decoder is robust
  • ALC starts at 0.0
  • Serial console access: minicom -D /dev/ttyACM0, root, 123


  • Setting time down to the second is weird. I used serial console and CLI instead.
x6100  xiegu  r1cbu