Matt thats the powerup sequence we used for the 40MHz PCM sets for our heavy but for different reasons, the transmitter stores the failsafes in this case, and transmits them a few seconds after it has been turned on and the receiver must be on first to do this, then the main robot power.

On one of our featherweights that uses the DX6 it uses a battery eliminator so we turn the transmitter on first and then plug in the link which powers the robots, both the weapon and speed controllers have thier own failsafes but I didnt know exactly how the DX6 systems work on power up but after the link is put in even moving the sticks does nothing for about 5 seconds so I guess it does not output anything until it sees the transmitter as Kane said, not sure if you have AR6000 receiver but we have the BR6000 and powering it up this way passes the tech check where they fire the weapon soilnoid to here the click, then turn off the transmitter and it clicks again, turning off, not sure what the channel is called but its the left & right movement on the right stick. Same happens on both channels on the left stick with the speed controller.