Hi all,  first off i've been reading through all these forums for several months, and i've found everyone to be quite helpfull and full of insight, so thanks for that. 


My build so far is quite simple APM 2.5 with the 900Mhz radio on a nitro heli.  the issue that i'm having is that no matter how i power the APM whether it be via USB or battery, the output to the servos has no power.  the APM boots up properly and everything seems fine, but no servo movement.  even in the mission planner it's showing an output signal to the servos.  so i took my trusty multimeter to the rail and found that the signal is in deed being sent to the servos just not the power.  i found that if i connect a seperate power source to the output servo rail then everything works as long as there is also another power source to the APM.  ie: the APM will not power up when i apply 5V to the output rail.  so the question is what might be wrong and could i apply 6V to my output rail and not fry the rest of the board?  i've included a few pictures of my setup just incase i've not hooked it up properly.

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To power the APM with one power source, connect the power to the output rail and make sure you have JP1 installed. Your description of the problem indicates that it is not.

JP1 is located by the output PWM connector near the C B A LED

Hey Bill,

Thanks for the reply,  I feel kinda stupid now that i've read the manual.  i put the JP1 on and have the whole board running on one source.


but quick question if i leave the JP1 disconnected can i power the output servos with 6V?  or will that fry the APM?

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