Can’t connect receiver

[Willlanoob]

Hay I’m having an issue connecting my rx (SPM4650)
I Have it soldered to the tx3 pad on the
Mamba F405
I have updated beta flight and still doesn’t work I’m quite new to this and don’t quite understand it all plz help

 

[RENOV8R]

Should all be explained here.

Spektrum SPM4650 | helpful user manual

SPM4650 helpful illustrated users guide & manual. Specktrum drone DMSX receiver with RSSI and 2 way telemetry which allows PID tuning directly on your TX

www.graysonhobbyshop.com