Problem with the spektrum port


Some versions of the controllers can have a problem with the spektrum port: the satellite receiver does not get enough power from the 3.3V internal voltage regulator, resulting in unstable operation (symptoms: signal interrupts, LED blinks randomly, on binding attempt system goes to reset). 
Possible workarounds:
1. To power the receiver from the external 3.3v power source.
2. To solder additional 3.3v LDO regulator into the controller. The best choice is 3-lead TO-92 package (for example, LP2950-33, L4931CZ33-AP, L78L33-ACZ).  Soldering additional LDO voltage regulator 3.3v