Getting Servos to Work

[FrightCrewLLC]

Hello all!

I'm new to the forums here and I'm having a little problem I was hoping some of you folks could help me out with.

I have a project that requires me to run multiple servos off a Prop 2 at the same time. Obviously the Prop 2 does not provide enough current for this to be possible, so I have an external 5 volt power supply (8.0 Amps) hooked up to a servo to test it. Trouble is, when everything is hooked up and the Prop 2 is activated, the servo doesn't move. It works fine when I run the single servo with the three pin connection on the board itself, so I know there's nothing wrong with my program. I've included a picture of what I've done so far here:

http://tinyurl.com/7o9ts9o

What am I missing? Clearly something isn't right.

Thanks in advance!

[JonnyMac]

I got an error when trying to view your picture (you seem to be pointing to an attachment on an email that cannot be accessed outside your Gmail account).

Things to check:
-- do you have common ground between your external power supply and the Prop-2?
-- you should only be using the W and B wires from each output
    * do not use the R wire as it have 5v from the board and you could have a power-supply conflict

[livinlowe]

My first thought would be the common ground like jon said

[JackMan]

Here's a simple diagram showing what Jon explained.