Help! Pairing Radiomaster Pocket with X-Cub 450mm

[lance wisher]

Hey everyone, I’m Lance and I’m pretty new to RC planes but I'm having a blast with my first plane - a Hobbyzone xcub 450mm. I just picked up a RadioMaster Pocket running EdgeTX and added an iRX4 Lite 4-in-1 module so I can fly my Spektrum recievers (DSM), like in my HobbyZone X-Cub 450 mm. Trying to get this combo to work has me stumped and I could really use some advice from anyone who’s gone down this road before.

I flashed the latest EdgeTX (v2.11.0) to my Pocket transmitter and copied over the SD card contents. I then downloaded and flashed the iRX4 Lite firmware in Serial-DSM-Auto mode with AETR air settings. On the plane side, I have looked into the fuselage but cannot find any manual bind button on the PCB. Every time I plug in the plane battery the receiver LED slow-blinks, which I understand means it’s waiting to bind—but when I try to bind from the transmitter by clicking [Bnd] in the external RF setup, the plane doesn't respond and the light keeps blinking instead of going solid like it does with the RTF transmitter that it came with. I’ve tried adjusting throttle trims, verifying SAFE mode is on Beginner, and even swapping sub-protocols (DSM2-22 ms, DSMX) but no luck.

Other stuff I've tried:

• Double-checked External RF settings (MULTI → DSM → Auto) and turned off internal RF.

• Made sure throttle stick is exactly at its lowest and SAFE switch isn’t in Expert.

• Used [Bnd] within 5 seconds of plugging in the plane’s LiPo, watched the module LED flash fast then go solid.

• Confirmed Mixer and Outputs screens have no blank lines for CH1–CH5.

• Range-tested at 2 m with [Rng] and saw the module’s red LED slow-blink after bind.

• Re-formatted SD, re-flashed module firmware (v1.3.4+), and removed any leftover Lua scripts that might interfere.

• Is there any hidden setting or sequence I’m missing to actually send channel data after bind?

• Could the plane’s receiver board be permanently set to an old GUID so it never “re-listens” for new binds?

• Has anyone had to modify the plane’s firmware or patch the PCB to force a manual bind since there’s no button?

I’d love to get this X-Cub up and flying—any pointers, troubleshooting steps, or even wild hacks are welcome.

Thanks in advance!!!

- Lance

[prikrylm]

Briefly.:
According to the manual page 8 (and my experience) you need to turn on the receiver (Rx) without any transmitter transmitting and wait until Rx starts blinking quickly - only at this moment is Rx in pairing mode. Then turn on the transmitter and pair.
If pairing requires throttle at minimum, you also need to check channel mapping - std AETR on Spektrum TEAR. Either the disable mapping switch turned off, or ensure throttle is at channel 1.
In addition, DSM uses a channel range from 1100 to 1900 ms, so it is a good idea to limit used channels in the servo menu to approx. +-80%