hfsdr

HFSDR: host software, firmware, and hardware design for the HFSDR USB device.

Getting started

Portable Mode (not connected to a PC)

1. Press the Rotary Encoder to
   1. Enable/ Disable FM Audio Out mode (on disabled, it plays a constant tone)
   2. Cycle through different LED modes

Connected to a PC

1. Go to the web ui
2. Connect & Pair a device
3. Set the frequency & gain
4. Pair the device again
5. Waterfall of the wireless world should start. If it doesn't look like this, unplug the device and try again

• User manual (slides): HFSDR User Manual
• Lain Themed Web UI lain-sdr-ui
• Host testing (Python probe, GNU Radio .grc examples, drivers, protocol): docs/host-guide.md

Troubleshooting

• USB / stream flaky: Unplug the board or reset it a few times. The host stack sometimes needs a power cycle before enumeration, WinUSB binding, or streaming stabilizes.
• Using with GNURadio/ Python Scripting: See the driver and probe sections in docs/host-guide.md.
• Reset: Do not hold the reset button for too long

Repository layout

Path	Contents
ch32v305/	Firmware (CH32V305). Build, flash, toolchain: ch32v305/README.md.
client-sw/	Host Python (hfsdr_probe, PyUSB helpers), GNU Radio blocks and examples (gr-hfsdr-lib, .grc).
docs/	host-guide.md — primary host-side documentation.
hardware/	KiCad project and related hardware files. (Will be published in a while)
scripts/	Helper scripts (e.g. udev 99-hfsdr.rules, Windows USB checks).
ui/	WebUSB Web UI (Svelte/Vite). Deployed build: homepage in ui/package.json.

Credits

1. rhgndf - hard carry schematic & everything inside actually
2. Hackin7 - Art, PCB rough layout & routing & some embedded
3. Hack & Roll Cursor Credits + Codex - allow us to do this while being overseas/ having full time jobs
4. https://github.com/ttrftech/CentSDR - Useful reference