Looking at it straight on and going left to right:
First slot on the left is Battery port. On older receivers, before they added the bind button, it was the "bind" port, and would be used for people flying with a battery pack instead of using a BEC or battery elimination circuit. From there, going to the right, It's
TAERGA -
Throttle on port 1,
Aileron on port 2,
Elevator on port 3,
Rudder on port 4,
Gear on port 5,
AUX1 on port 6. All can be reprogrammed via the computerized programming on almost all of the Spectrum radios, though, so it's possible to have the Rudder on port 2, ailerons on port 5, etc...It's kind of a pain to reprogram, though, so I generally leave it.
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