I know Nothing about the dx3r Tx
the yellow wire is on Ch3?
and your tx ch3 needs to be on when you turn the rc on.
"For My radio all i needed to do was....
just plug it in to Ch1 on the RX
the yellow wire to Ch3 on the RX
Flip the switch on the Gyro to REV
Turn on the TX
turn on the Rc.. Wait for the Gyro to set its self about 3 seconds"
if the gyro DON'T see a signal on ch3 it will not initialize .
