I made these boards up for my personal use but if any of you guys are gonna do some video builds I can sell you one. Makes the video builds much much easier and faster to assemble. I got Gary's permission to use the Sister Board's circuit before I done these as well. Basically it is a PRE Amp board like a KIT98 and the 2 sisters boards all on one board. Also has the exchanger stuff on it as well. Has a 6.8 ohm resistor built in so there is no need to put one in the yellow line from the exchanger as well. It is basically plug and play!!! Across the top you will see 13 holes. All you do is solder in the wires from the proper thing. No more jumpers from one sister board to the other.
12v+
12v-
mic+ to camera
mic- to camera
array+
sound wire from BF board's 5 hole
BF ground wire from the BF board 4 hole
array-
array wire from BF board 2 hole
exchanger's yellow wire
exchanger's black wire
exchanger's red wire
exchanger control wire from BF board 3 hole

Down in the lower left corner you will see the 2 holes for the external mic + and mic- coming in
And to the right side of the board you will see 4 holes. These are for the black and gray wires coming from the exchanger control board and you can add 2 wires to go out to the camera and tie into your servo to the exchanger inside the camera
These are super simple to hook up and use.

Could I use this to trigger my Canon T3i HD video? I am new to all of this, and I am not sure what I need. thanks.

I don't think this is necessary for you with your Canon(or most dslr) since they have many of the functions and hookups(for external mics and remotes, etc) built in. Perhaps pm one of the guys such as bkeiffer who has just been working with the t4i video and see what he did.

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