SDR# Frequencies.xml File Format Explained

SDR# (SDR Sharp) stores all scanned and saved frequencies inside a single XML file named Frequencies.xml, located in the SDR# program folder. This page explains the structure of that file and how SDR# Frequency Manager reads, edits and saves it safely.

Where is Frequencies.xml stored

The file lives in the same directory as SDRSharp.exe. On a typical install that is something like C:\Program Files\Airspy\SDRSharp\ or wherever the user extracted the SDR# distribution. Each Frequency Manager entry inside SDR# is serialized as an XML element with attributes for name, frequency, detector mode, bandwidth, shift, group and several boolean flags.

Core columns

  • Name – human-readable label shown in SDR#.
  • Frequency (Hz) – center frequency in hertz.
  • Detector – demodulation mode (NFM, WFM, AM, USB, LSB, CW, DSB, RAW).
  • Bandwidth (Hz) – filter bandwidth.
  • Shift (Hz) – frequency shift for offset receivers.
  • Group – logical grouping label.
  • Favourites / HF / Scanned – boolean flags.
  • Note – free-form text annotation.

Why a .sdrfe sidecar exists

The stock SDR# schema does not preserve some metadata that SDR# Frequency Manager adds for usability – for example category title rows used to organize large lists. To keep that information without breaking SDR#, the application writes a sidecar file with the same name and a .sdrfe extension in the same folder. This sidecar must stay next to the main XML. If you move or delete it, formatting is lost but the actual frequencies remain.

Editing best practices

  • Always close SDR# before editing the file with an external tool.
  • Make a backup copy of Frequencies.xml (and the .sdrfe sidecar if present) before bulk operations.
  • Use SDR# Frequency Manager to avoid hand-editing XML, which is error-prone.
  • If you add or delete entries from SDR# directly while the file is open in Frequency Manager, simply reopen the file – changes are detected and merged on next load.

Download SDR# Frequency Manager

Skip the manual XML editing and use the dedicated tool: SDR# Frequency Manager is free for personal and non-commercial use and runs on Windows 11/10/8. See the download page for the current version, size and checksum.