• FM
  • Intermediate
  • 5 min
  • Serial CLI

Recipe · Intermediate · FM

How to scan the FM band with Si4713

The FM mode can sweep and visualize activity across the FM band through a Si4713 module. This recipe focuses on observation, not broadcasting.

FM transmitter module with radio waves.
Sweep the band, trace one frequency, and use waterfall for visual context.

Wiring View

Si4713 BP SDAI2C SDASCLI2C SCLRSTBP GPIOVCCmodule supplyGNDBP GND
Generated from the wiring summary: Si4713 to BP.
Step 1

Commands

Run the commands below after selecting the right Bit Pirate mode and confirming the wiring.

Result

What success looks like

The sweep shows local peaks and trace follows the selected frequency strength. If every channel looks flat, check antenna/module wiring.

Troubleshooting

  • Reset pin not configured.
  • SDA/SCL swapped.
  • No antenna or poor module placement.
  • Expecting broadcast output while using scan commands.

Next steps

  • Use trace [freq] to watch one station/frequency.
  • Use waterfall for a visual overview.
  • Only enter broadcast in a legal controlled setup.

FM band scan FAQ

What does FM sweep show?

It scans the 88 to 108 MHz FM band and estimates activity so you can see likely local stations or busy parts of the band.

Why do all frequencies look flat?

The Si4713 may not be configured, the reset pin or I2C wiring may be wrong, the antenna may be missing, or the local signal level may be too low for the setup.

Does scanning transmit FM?

No. sweep, trace and waterfall are observation workflows. Broadcast operations are separate and should only be used legally at very low power in a controlled setup.

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