Front Panel LED Indications - flexradio/smartsdr-api-docs GitHub Wiki

Color Meaning
SOLID BRIGHT RED Transmitting on PA
SOLID ORANGE Transmitting on XVTR port with low power
SOLID DIM RED Transmit engaged, but all interlocks not resolved (will not emit RF)
SOLID PURPLE Updating software
FLASHING YELLOW GPS in warmup
SOLID YELLOW GPS in holdover (lost satellites)
SHORT FLASH BLUE GPS locking
LONG FLASH BLUE GPS in hold phase mode
SOLID BLUE GPS locked
SOLID GREEN Receive
FLASHING GREEN Radio booting
SOLID AMBER Radio off, GPS or OCXO powered for stability
FLASHING RED "S" Flashing a Morse "S" in Red indicates boot failure
OFF Radio off, oscillators off