Good morning, I have a Radiomaster TX16s max, I keep getting a warning RF critical. I use spektrum AR410 and AR620 rx’s. I have only recently kept getting this warning. I recently updated the firmware to v2. 10.5. I have reported this to Radiomaster thereselves, there response was to update the 4in1 protocol, which I have with no change. I love the radio and it’s functionality. I have now gone back to v2. 9.3 firmware, to a point where I didn’t get the issue, but I now get the warning. I have turned all the telemetry off, in the settings. I want to get back to using the tx. Can you help please?
Kind regards
Stuart
The RF critical warnings you’re experiencing are often considered false alarms by users. The issue occurs because Spektrum receivers don’t send true RSSI (signal strength) information, so OpenTX/EdgeTX uses the telemetry signal strength to estimate RF levels. This can create inaccurate readings that trigger warnings, even though the actual control link may still be functioning adequately [Aeromodellers Forum] [GitHub - Multiprotocol TX Module].
Solutions
Option 1: Adjust Warning Settings
- Consider adjusting the RSSI and telemetry alarm thresholds in EdgeTX/OpenTX.
- Navigate to telemetry settings to set low and critical warning levels that better align with actual signal strength levels reported by users [Reddit - RC Planes].
Option 2: Telemetry Management
- If preferred, you can turn off telemetry alerts entirely [Aeromodellers Forum].
- Many pilots successfully flew without telemetry in earlier setups, but be sure this approach aligns with your setup and flying style.
Option 3: Range Testing
- Before flying, perform a range test with your model aircraft.
- During the range test, check that all control surfaces respond accurately across distances. If you observe consistent control during testing, you may conclude that the RF warnings are not reflective of a real-time control issue [Aeromodellers Forum].
Important Notes
Many users report that the control link remains strong, sometimes up to 1200 meters, even when RF warnings appear. However, keep in mind that the warnings result from how the TX16S interprets telemetry from Spektrum receivers and not necessarily from a real performance issue [GitHub - Multiprotocol TX Module].
Firmware updates have yet to fully address this compatibility difference because it stems from how Spektrum receivers communicate with non-Spektrum transmitters. With a successful range test, you may confidently proceed with your setup, though it’s always wise to remain cautious and continue monitoring firmware updates for any improvements [YouTube - RF Signal Critical on Spektrum RX and TX16S].
Hello Stuart,
Based on the search results, this is a known issue with Radiomaster TX16S and Spektrum receivers, and there are several ways to address it:
Understanding the Issue
The RF critical warnings you’re experiencing are actually false alarms. The issue occurs because Spektrum receivers don’t send true RSSI (signal strength) information, and instead, OpenTX/EdgeTX uses the telemetry signal strength to determine RF levels12. This creates inaccurate readings that trigger warnings even when the actual control signal is perfectly fine.
Solutions
Option 1: Adjust Warning Settings
Disable the RSSI and telemetry alarms in EdgeTX/OpenTX
Navigate to telemetry settings and modify the low and critical warning levels to more accurately represent the actual signal strength3
Option 2: Telemetry Management
Completely deactivate telemetry functionality1
This won’t affect your control capabilities, as many pilots operated successfully without telemetry in the past
Option 3: Range Testing
Perform a proper range test before flying
If the control surfaces respond correctly during the range test, you can safely ignore the RF warnings1
Important Notes
The control link is actually much stronger than the warnings suggest. Users have reported successful control at distances up to 1200 meters even while receiving these warnings2. The issue is purely related to how the TX16S interprets the telemetry data from Spektrum receivers, not an actual problem with the radio’s performance or range1.
The recent firmware updates haven’t resolved this issue as it’s inherent to how Spektrum receivers communicate with non-Spektrum transmitters2. You can safely continue using your radio by implementing one of the solutions above.
How would you rate our customer service?
Best,
Isel 
Unmanned Tech