Quansheng UV-K5 Firmware
The Quansheng UV-K5 is a budget handheld transceiver that has gained enormous popularity in the amateur radio community, not for its stock capabilities, but for its open and hackable architecture. A community of developers has reverse-engineered the radio's firmware and produced custom builds that dramatically expand the radio's functionality.
Why Custom Firmware?
The stock UV-K5 firmware is functional but limited. Custom firmware unlocks capabilities that the hardware supports but the factory software does not expose:
| Feature | Stock Firmware | egzumer/OEFW |
|---|---|---|
| Frequency range (RX) | 50--520 MHz | 18--1300 MHz |
| Spectrum analyzer | No | Yes |
| AM reception | Limited | Full support |
| SSB reception | No | Yes (with limitations) |
| Channel memory | 200 | 200 |
| Scanning speed | Slow | Significantly faster |
| Custom boot screen | No | Yes |
| S-Meter accuracy | Poor | Improved |
| Squelch levels | Basic | Fine-grained |
| FM broadcast radio | Yes | Yes (improved) |
Popular Firmware Options
egzumer Firmware (Recommended for Beginners)
The egzumer firmware is a fork of the original open-source OEFW (Open Edition Firmware) project. It is widely considered the most stable and feature-rich option for general use.
Key features:
- Spectrum analyzer with adjustable bandwidth
- Improved AM/FM reception
- Faster scanning
- Configurable squelch levels (0--9)
- Custom startup logo support
- NOAA weather channel reception (where applicable)
- Improved S-meter calibration
- Backlight timeout options
- Copy/paste channel settings
Repository: https://github.com/egzumer/uv-k5-firmware-custom
OEFW (Original Open Edition Firmware)
The original open-source firmware project that spawned most forks. Development has slowed as most contributors have moved to forks like egzumer's.
Repository: https://github.com/DualTachyon/uv-k5-firmware
RE Firmware (Tunas1629)
A more experimental fork focused on pushing the hardware limits. Includes features like:
- SSB demodulation (narrow-band)
- Si4732 chip direct control
- Extended modulation options
- Experimental digital mode decoding
Best suited for advanced users comfortable with potential instability.
What You Need
Before flashing, gather the following:
- Quansheng UV-K5 radio (or UV-K5(8), UV-K6, UV-5R Plus -- check firmware compatibility notes)
- USB-C programming cable -- The Quansheng-specific cable with the Kenwood-style 2-pin connector on the radio end and USB-C on the computer end. Generic Kenwood cables may also work, but the official cable is recommended.
- A computer running Windows, macOS, or Linux
- The firmware binary file (.bin) downloaded from the firmware project's GitHub releases page
- A flashing tool (see below)
Flashing Tools
Web Flasher (Easiest Method)
The community has built browser-based flashing tools that require no software installation:
UV-K5 Web Flasher: https://egzumer.github.io/uvtools/
This tool runs directly in your web browser using the Web Serial API. Requirements:
- A Chromium-based browser (Google Chrome, Microsoft Edge, Brave). Firefox does not support Web Serial.
- USB cable connected and recognized by your OS
k5prog (Command Line)
For Linux users or those who prefer command-line tools:
# Clone the repository
git clone https://github.com/sq5bpf/k5prog.git
cd k5prog
# Build
make
# Flash firmware
./k5prog -F -YYY -b firmware.binThe -YYY flag confirms you want to proceed (triple-Y to prevent accidental flashing). The -F flag specifies a firmware flash operation.
QUV-K5 Toolbox (Windows GUI)
A Windows-based GUI tool that provides firmware flashing along with other configuration options. Download from the project's releases page on GitHub.
Step-by-Step Flashing Guide
Step 1: Download the Firmware
- Navigate to the firmware project's GitHub releases page (e.g.,
https://github.com/egzumer/uv-k5-firmware-custom/releases). - Download the latest
.binfile. Pay attention to the version notes -- some releases target specific hardware revisions. - Save the file somewhere you can easily find it.
Step 2: Back Up Your Current Firmware
WARNING
Always back up your existing firmware and channel data before flashing. If something goes wrong, you will need the backup to restore your radio.
Using the web flasher:
- Connect your radio to the computer via the USB programming cable.
- Turn the radio off.
- Open the web flasher in Chrome/Edge.
- Click Read EEPROM (or the equivalent backup option).
- Hold the PTT button while turning the radio on. The radio should enter bootloader mode (the screen will be blank or show a minimal display).
- Click Connect and select the serial port corresponding to your cable.
- Wait for the backup to complete and save the resulting file.
Step 3: Flash the New Firmware
- With the radio still in bootloader mode (or re-enter it by turning off, holding PTT, and turning on).
- In the web flasher, click Flash Firmware.
- Select the
.binfile you downloaded. - Click Connect if not already connected.
- Wait for the flashing process to complete. Do not disconnect the cable or turn off the radio during flashing. This process typically takes 30--60 seconds.
- Once complete, the tool will confirm success.
Step 4: Verify the Flash
- Turn the radio off and back on normally (without holding PTT).
- The radio should boot with the new firmware. You may see a new boot screen or version information.
- Check that basic functions work: tune to a known frequency, verify transmit (into a dummy load if possible), check that the spectrum analyzer and other new features are accessible.
Step 5: Restore Your Channels (If Needed)
Custom firmware may or may not preserve your existing channel memories. If your channels are gone:
- Use the web flasher's Write EEPROM function to restore from your backup, or
- Re-program channels using CHIRP (see the CHIRP Programming Guide)
Troubleshooting
Radio won't enter bootloader mode
- Make sure you are holding PTT before and while turning the radio on.
- Try a different USB cable. Some cables are charge-only and do not carry data.
- Check that your OS recognizes the USB serial device. On Windows, you may need to install a driver (typically a CH340 or Prolific PL2303 driver). On Linux, the device should appear as
/dev/ttyUSB0or/dev/ttyACM0.
Flashing fails or times out
- Close any other applications that might be using the serial port (CHIRP, terminal emulators, etc.).
- Try a different USB port. Avoid USB hubs -- connect directly to the computer.
- Reduce the baud rate if the flashing tool offers that option.
- On Linux, ensure your user has permission to access serial ports:
sudo usermod -aG dialout $USER(then log out and back in).
Radio is bricked (won't turn on or stuck on boot)
- Don't panic. The bootloader is stored in a protected area and is very difficult to overwrite.
- Re-enter bootloader mode (PTT + power on) and flash the stock firmware or a known-good custom firmware.
- If the bootloader itself is corrupted (extremely rare), the radio will need a JTAG/SWD recovery, which requires specialized equipment.
Audio quality is different after flashing
- Custom firmware may have different default audio processing settings. Explore the firmware's menu options for squelch type, bandwidth, and audio gain settings.
Tips and Best Practices
- Stay on stable releases. Nightly or development builds may have unresolved bugs. Unless you are specifically testing, stick with tagged releases.
- Read the changelog before updating. New firmware versions occasionally change menu layouts or default settings.
- Join the community. The UV-K5 modding community is active on Reddit (r/QuanshengUVK5), Discord, and GitHub. These are excellent resources for troubleshooting and discovering new features.
- Calibration matters. After flashing, you may want to recalibrate the S-meter and TX power levels using the firmware's built-in calibration tools and a power meter.
- Remember the legal limits. Custom firmware can unlock wide-band transmit. Just because you can transmit on a frequency does not mean you may. Always operate within your license privileges.
Contributors
IUU6