FM Radio
FM Radio
Overview
The RT-900 includes a built-in FM broadcast receiver using the RDA5807 chip. This is a completely separate subsystem from the main radio — it operates independently of the VFO frequencies and has its own tuning, presets, and volume. You can listen to FM broadcast stations without occupying the main radio's receive path.
Frequency Bands
The RDA5807 supports two FM band configurations selectable via the FM menu:
| Band | Range | Notes |
|---|---|---|
| Standard | 76–108 MHz | Worldwide FM broadcast band |
| Extended | 65–76 MHz | OIRT band — used in Eastern Europe and parts of Asia |
Using FM Mode
There are two quick ways to enter FM mode:
- Long-press 0 — The default long-press shortcut for the 0 key opens the FM radio directly.
- PF2 side button — The default short-press action for PF2 (middle side button) is FM Radio.
You can also reassign the side buttons via the menu:
menu 46— PF2 key (short press)menu 47— PF2 key (long press)menu 48— PF3 key
Set any of these to the Radio function to get one-button access to the FM receiver from the main screen.
Presets
Up to 30 FM station presets can be stored in EEPROM. Presets persist across power cycles.
- Tune to the desired station frequency.
- Save it to one of the 30 preset slots using the save function in the FM menu.
- Recall presets by stepping through them with
UPandDOWNwhile in FM mode.
Auto-Seek
The RDA5807 chip includes hardware-assisted station seeking. Auto-seek automatically steps through the band and stops at the next frequency where the chip detects a station with sufficient signal quality.
Hold UP to seek to the next station up the band, or hold DOWN to seek downward. The seek wraps around at band edges.
FM Audio
FM broadcast audio plays through the radio's main speaker. Volume is controlled independently from the main radio volume — adjusting one does not affect the other. The RDA5807 outputs stereo audio internally, but the RT-900 mixes it to mono for the single speaker.