Flash the value
An OSD alarm is the number that makes one element flash. The card footer says an alarm makes its OSD element flash, and that the values are always metric, whatever the OSD units are set to.
Altitude starts at 100 m. The hint says it flashes above that, and that 0 means off. The picture holds the alarm at 100 m and a height of 50 m, so the lamp says Steady. Raise the height past 100 m and it flashes. Set the alarm to 0 m and a high height stays steady.
The other alarms on the same card use the same idea, with their own direction. RSSI and link quality flash below. Distance flashes when you are farther from home. A 0 on the ones whose hint says so turns that flash off.
Free. Hardware connections need Chrome or Edge on a computer; phones use the FlySpark app.
- Free
- Nothing to install
- Demo without hardware
In short
An INAV OSD alarm makes its element flash. Altitude starts at 100 m and flashes above that height. Set the alarm to 0 m and it stays off.
Key facts
- The Alarms card says an alarm makes its OSD element flash, and the values stay metric whatever the OSD units.
- Altitude starts at 100 m and flashes above that. 0 m is off. The picture uses that rule.
- RSSI starts at 20% and flashes below it. Link quality starts at 70% and also flashes below it.
- Distance starts at 1000 m and flashes farther from home. Below home starts at 5 m. Both are off at 0.
- Flight time starts at 10 minutes. Current starts at 0 A, which is off, and flashes above the value you set.
- SNR starts at 4 dB and flashes at or below it. The dBm alarm starts at 0, which the hint calls off.
- Airspeed low and high start at 0 km/h, which the hints call off. G-force starts at 5.0 g.
- Chrome or Edge uses USB or Bluetooth. iPhone has no USB host.
Betaflight
INAV
ArduPilot
PX4- BLHeli_S
Bluejay
AM32
ExpressLRS
EdgeTX
DroneCAN
MAVLink
Try it
Flash above the line
The altitude alarm starts at 100 m. The picture flashes above that height, and 0 m leaves it steady.
Steady
Alarm 100 m
FlySpark
Features
- 01
100 m, then it flashes
Altitude starts at 100 m, from 0 to 10000. The hint says it flashes above this. The picture stays steady at 100 m and flashes at 101 m.
- 02
0 m is off
The altitude hint says 0 means off. In the picture an alarm of 0 m stays steady at 200 m.
- 03
RSSI flashes below 20%
RSSI starts at 20%, from 0 to 100. The hint says it flashes below this, so 20% itself is not below the line.
- 04
Link quality starts at 70%
Link quality starts at 70% and flashes below that. The hint names Crossfire at 70% and Tracer at 50%.
- 05
Farther than 1000 m
Distance starts at 1000 m and flashes when you are farther from home than that. 0 m is off.
- 06
Always metric
The footer says the alarm values stay metric whatever the OSD units are. The demo units start on metric.
Above the altitude
Altitude alarm is in metres, from 0 to 10000, and the demo is 100. The hint says it flashes above this, and that 0 means off. The picture's height starts at 50 m with the alarm at 100 m, so the lamp says Steady. At 100 m it is still steady, because the hint says above, not at the number. At 101 m the lamp says Flashing. Set the alarm slider to 0 and the lamp says Off, including at 200 m.
The picture only runs the height to 200 m so the 100 m line is easy to cross. The field on the card goes on to 10000 m. Below home is a separate field. It starts at 5 m, from 0 to 10000, and the hint says it flashes this far below the arming point. 0 means off. That 5 m is on in the demo, so a descent of 5 m below where you armed will flash even while the altitude alarm is still at 100 m.
Distance starts at 1000 m, from 0 to 50000, in steps of 50. The hint says it flashes farther than this from home, and that 0 means off. Current starts at 0 A, from 0 to 255. The hint says it flashes above this, and that 0 means off, so the demo does not flash on current until you set a number above 0. Flight time starts at 10 minutes, from 0 to 600. The hint says it flashes once you have been armed that long, and that 0 means off.
Below the link
RSSI starts at 20%, from 0 to 100. The hint says it flashes below this. A reading of 20% is not below 20, so the flash starts at 19% and under. Link quality starts at 70%, from 0 to 100. Its hint says it flashes below this, and it names Crossfire at 70% and Tracer at 50%. The demo is already the Crossfire number. SNR starts at 4 dB, from -20 to 10. The hint says it is the Crossfire signal-to-noise and that it flashes at or below this, so 4 dB itself flashes, unlike the RSSI line.
RSSI dBm alarm starts at 0, from -130 to 0. The hint says it flashes below this, and that 0 means off, so the demo does not flash on dBm. dBm shown as 100% starts at -30 dBm, from -50 to 0. dBm shown as 0% starts at -120 dBm, from -130 to 0, and the hint calls that the receiver sensitivity. Those two scale the element. They are not the flash threshold.
Airspeed low and airspeed high both start at 0 km/h. The low hint says it flashes below this, as a stall warning, and that 0 means off. The high hint says it flashes above this, and that 0 means off. Both step by 5 km/h. G-force starts at 5.0 g, from 0 to 20, in steps of 0.5. The card does not add a hint for when that one flashes. Axis g-force low starts at -5.0 g and axis g-force high at 5.0 g, each from -20 to 20.
IMU temperature low starts at -20 °C and high at 60 °C. Barometer low and high start at the same -20 °C and 60 °C. The barometer low hint says it flashes that element below this. ESC temperature low starts at -20 °C and high at 90 °C. The footer still applies: an alarm makes its element flash, and these numbers stay metric even if the units picker is not on metric. The demo units picker starts on metric.
Where you set it
Open the OSD tab on INAV and find Alarms. Chrome or Edge connects over USB or Bluetooth. Android adds Wi-Fi. iPhone uses Bluetooth or Wi-Fi and has no USB host. Set the altitude, the link and the distance you actually want to notice, then save. A 0 on a field whose hint says 0 means off will not flash that element.
The horizon is a different card. OSD horizon is the camera uptilt and the line in the picture. It does not set these flash thresholds. A power limit that cuts the throttle is also a different card. This one only flashes the OSD element.
FlySpark
Set the altitude flash
Open Alarms
On INAV, open the OSD tab and find Alarms. The footer says an alarm makes its OSD element flash.
Read 100 m
Altitude starts at 100 m. The hint says it flashes above that, and that 0 m means off.
Read the link lines
RSSI starts at 20% and flashes below it. Link quality starts at 70% and flashes below it. The hint names Crossfire at 70% and Tracer at 50%.
Leave a 0 where you want silence
Current, the dBm alarm, flight time, distance, airspeed and the altitude alarm all say 0 means off. Below home starts at 5 m, not at 0.
Troubleshooting
Common problems and fixes
Problem
The altitude element never flashes
Fix
It flashes above the alarm, and the demo is 100 m. A height of 100 m is not above it. 0 m means off, so a cleared alarm never flashes.
Problem
RSSI flashes while the number still looks fine
Fix
RSSI starts at 20% and flashes below that. 19% flashes. 20% does not, because the hint says below, not at the number.
Problem
It flashes 5 m under the arming point
Fix
Below home starts at 5 m. The hint says it flashes that far below the arming point. Set it to 0 m to turn that one off.
Problem
The numbers did not switch to feet
Fix
The footer says alarm values are always metric, whatever the OSD units are. The units picker does not convert these fields.
FAQ
Frequently asked questions
What is an INAV OSD alarm?
A threshold that makes one OSD element flash. The footer says the values stay metric whatever the OSD units are.
When does altitude flash?
Above the alarm. It starts at 100 m. 100 m is steady. 101 m flashes. 0 m means off.
When does RSSI flash?
Below 20% in the demo. The field runs from 0 to 100. The hint says below, so 20% itself does not flash.
What link quality does the demo use?
70%. It flashes below that. The hint names Crossfire at 70% and Tracer at 50%.
Does 4 dB of SNR flash?
Yes. SNR starts at 4 dB and the hint says it flashes at or below this, which is stricter than the RSSI line.
Why does it flash just under where I armed?
Below home starts at 5 m. The hint says it flashes that far below the arming point. 0 m turns it off.
What distance starts the flash?
Farther than 1000 m from home. The field runs from 0 to 50000 m, in steps of 50, and 0 m means off.
Does current flash in the demo?
No. It starts at 0 A, and the hint says 0 means off. Set a number above 0 and it flashes above that.
Are the alarms in feet if I pick imperial?
No. The footer says the values are always metric, whatever the OSD units are. The demo units start on metric.
Can I set this in Chrome?
Yes, on INAV. Chrome or Edge uses USB or Bluetooth. Android adds Wi-Fi. iPhone uses Bluetooth or Wi-Fi and has no USB host.
References
Sources
The official documentation behind the background facts on this page.
- INAV OSD notesINAV · github.com
- INAV settingsINAV · github.com
- INAV ConfiguratorINAV · github.com


