INAV Troubleshooting - Quick List

1. Flight Control Board Assembly - Take care when soldering. Look for solder bridges, reverse polarity connections and bent pins. Check voltages with a multimeter.

2. Connect the board to INAV via USB - If the board is not detected make sure the required USB drivers are installed on your computer.

3. FIRMWARE - Make sure you are using the correct firmware target for your board. 

Don't guess, check the FC documentation. 

eg. SpeedyBee F405 Wing Mini does NOT use the SPEEDYBEEF405MINI INAV target

4. Check that the animation moves the same way as the board when mounted in your plane.

Set FC orientation using the Alignment Tool.

5. MIXER - Select your Platform Type and Mixer Preset to load motor and servo mixing. 

IMPORTANT - Don't do any of this mixing in the radio. The FC takes care of all the mixing.

The radio must only have the basic INAV MIX, no matter what sort of craft you are flying. 

INAV MIX for the radio. 

Ch1 100 AIL

Ch2 100 ELE

Ch3 100 THR

Ch4 100 RUD

Ch5 ARM 

Other channels for flight modes

6. OUPUTS - Enable Motor and Servo Output
Choose ESC Protocol and Servo Refresh Rate. Use STANDARD and 50 Hz if they are unknown.

You can check if the motor works and calibrate the ESC using the sliders on this page.

7. PORTS - Enable a UART for Serial RX (Also GPS and FPV if required) Only one UART for each.

SBUS Rx with F405 boards require Serial RX to be on UART2.

8. CONFIGURATION - Turn On "GPS for Navigation and Telemetry" (if GPS will be used)

9. FAILSAFE - Only set as RTH for GPS setups.

Arming will be prevented if RTH is set for a non-GPS setup.

10. RECEIVER - Connect the receiver to the Serial RX UART 
Choose the Channel Order for your type of radio. AETR is most common
Choose the Serial Receiver Provider for your receiver - CRSF for ELRS, SBUS for SBUS etc.

Channel bars for Roll, Pitch, Yaw and Throttle must move to the RIGHT when moving the radio sticks UP and RIGHT.
Also check that all your mode switches show a response on the relevant channel bars

11. MODES - Configure Modes and assign to channels. 

ACRO will be active if no other mode is selected. 

12. ARMING PROBLEMS - Read the Arming Flags along the bottom of the INAV window and in your FPV goggles. Also in the CLI, type STATUS for more clues.

Arming is only possible in ACRO, ANGLE or MANUAL modes, and GPS must have acquired at least 6 satellites and a 3D lock.

To bypass the Arming Flags, hold the throttle stick down and yaw right while arming. 

BEWARE this is for troubleshooting only and is not a safe flying condition. 

Disconnect the battery to clear Arming Flag bypass.

FLYSKY Paladin PL18 Ultra internals

 

4 rubber pads and 8 screws / bolts to remove the back 

2 x Patch antennas

No ratchet spring on the throttle

Wiring for Eachine Sphere Link - Open IPC HD FPV

The two G and two 9V wires from the VTx can be combined into one G and one 9V for the FC HD FPV UART input.

Tx and Rx wires from the camera also go to the FC HD FPV UART. Camera ground wire not required when connected like this.

3D print file for mount

My YouTube review video

Cardboard Plank - 30% Corvo

 

Roughly scaled 30% dimensions of the 2m CORVO

Video of my version with 185mm chord - https://www.youtube.com/watch?v=hL1W1PqLMDw

My INAV OSD for HD FPV

 Here is how I arrange my HD FPV OSD for DJI and Walksnail Avatar gear and ELRS RC link

DJI Vista / Runcam Link / Caddx Air Unit.  OSD overlayed using the WTFOS Chrome web tool

Walksnail Avatar.  OSD overlayed using the WalkSnail OSD App

Link to the Diff file for this layout - https://drive.google.com/file/d/1mwzIve5VPeCUxOykSMxM8u7kcGjdz56K/view?usp=sharing

Beginners RC and FPV gear for 2025

Here are some suggestions for the best beginners RC and FPV gear in 2025.

I am recommending radios with EdgeTX operating system and ExpressLRS RF link for the best future proofing.  This gear will be suitable for beginners and basic models right through to advanced users. 

ExpressLRS has now matured enough to be a reliable RC link system with superior range and link security. I would recommend using an ELRS radio with ELRS receivers, then adding an external 4in1 Multiprotocol Module for non-ELRS receivers.

RC Gear

Transmitters

Radiomaster Pocket ELRS

The Pocket is the cheapest and smallest radio but has all the functions and range of much more expensive systems. It has two 3 pos switches, a latching button, two momentary buttons and a slider on the top right. 

The antenna is fixed but able to rotate and fold away.

The screen is quite small which might be a problem for aging eyes.

Maximum output power of 250mW gives range of several km.

Radiomaster Boxer ELRS

The Boxer is closer to a normal sized radio with longer battery life, bigger screen and more switches. Two 2 pos, two 3 pos switches, one latching button, one momentary button and two pot knobs.

Output power of 1W gives range of tens of km. 

Receivers

Radiomaster ER PWM receiver range

The ER ELRS receivers have PWM pins for each channel and are designed to operate servos directly. 

Range of several km is possible with the Pocket and Boxer radios.

4, 6 and 8ch receivers are available, some with a barometer for vario feedback and battery monitoring.

Radiomaster RP serial receiver range

The RP ELRS  Serial receivers are designed for use with Flight Control Boards where a serial connection is required.

Serial connection means all 16 channels are sent down one wire.

Analog FPV Gear

The following gear is all standard definition analog because it is much cheaper than Digital HD. It is best to learn FPV using the cheaper analog systems then step up to digital later.

Goggles / Screen

The dual screen goggles like Skyzone or Fatshark are too expensive for beginners and it's best to save your money for future digital goggles purchase.

Eachine EV800D single screen goggles

These are a good compromise between cost and features. The screen can be detached from the goggles and used just as a screen. It has built in DVR recording and dual antennas.

FPV cameras

Runcam Phoenix 2 

This is my favourite analog FPV camera with 4:3 and 16:9 aspect ratio and great picture quality. The lens has a nice wide angle view.

There are many other camera options and anything similar will work for FPV as long as you pay attention to the required input voltage. Some cameras can only handle 5V and others can handle a wider range.

I prefer 16:9 aspect ratio and a wide angle lens (2.1 - 2.5mm) for use on fixed wing models.

Video Transmitters (VTx)

There are so many options for VTx that it's hard to narrow down the choice. 

I would avoid the ultra high power VTx. More than 1W power is just not necessary for normal FPV.

Anything with 1W or less is all you need for a few km of range. More range is best achieved with a high mounted directional receiver antenna, rather than pumping out more power.

You may also need to buy an antenna for the VTx. Take note of the antenna connection style such as SMA, RP-SMA, MMCX, uFL.

Here are some suggestions

AtomRC TX800 

AKK TS5832S 

AKK X2 

All-In-One units (AIO)

Eachine TX05 AIO FPV 

The cheapest and easiest entry to FPV is to use an AIO camera and VTx

They are not the best quality or range but you just have to supply power (usually 5V) and find the channel in your goggles.

They can also be easily swapped from model to model.

HD video cameras

For high quality onboard video recording here are some great options. 

Runcam Thumb 1080 and Thumb Pro 4k

The Thumb cameras are small and light weight but can record excellent video. They don't have an internal battery and require 5V input to operate. This can come from the receiver or another 5V source.

They have a gyro built in and can record a motion data file to be used for Gyroflow stabilised video.

Runcam 2 4k

Has a removable battery, so power from the model is not required. If you remove the battery and connect to the VTx it can also be used as an analog FPV camera as well as 4k HD recorder.