Mods by valekrus:

• https://whosmatt.github.io/uvmod/
• https://github.com/valekrus/uvmod-russian

Mods by piotr022:

• https://github.com/piotr022/UV_K5_playground?tab=readme-ov-file
• https://github.com/piotr022/UV_K5_playground/releases/tag/release-78

Mods by amnemonic:

• https://github.com/amnemonic/Quansheng_UV-K5_Firmware
• https://github.com/amnemonic/Quansheng_UV-K5_Firmware/tree/main/uvmod_kitchen

Mods by Tunas1337:

• https://github.com/Tunas1337/UV-K5-Modded-Firmwares

Flash Software:

• https://github.com/sq5bpf/k5prog

Forum:

• https://4pda.to/forum/index.php?showtopic=1071343

Advanced spectrum analyzer.
Mods _k5_OnlyReceiverSpectrum, _k5_TXRXSpectrum from https://whosmatt.github.io/uvmod/
Starts with the flashlight button. Before starting, either turn off the noise reduction (SQL to 0) or turn on the monitoring mode.

• Up / down - frequency change,
• 1/7 - sensitivity (measurement time),
• 2/8 - frequency step,
• 9/3 - zoom in / out,
• • / F (hold) - noise reduction level,
• 5 - backlight,
• 0 - ignore frequency,
• EXIT - exit.
  After exiting, open the menu to refresh the screen. By @fagci, v66.

Simple spectrum analyzer:
Mods _k5_OnlyReceiverSpectrum_Simple, _k5_TXRXSpectrum _Simple from https://whosmatt.github.io/uvmod/
Starts with the flashlight button.

• Up / down (hold) - change the center frequency,
• 1/7 - increase / decrease resolution,
• 8/2 - zoom in / out,
  PTT / EXIT - exit.
  After exiting, open the menu to refresh the screen. By @piotr022, v78.

Samples:

• https://www.youtube.com/playlist?list=PL67vBSofOrHMyXOEhonOzQz5gJzsZFiDq