First I'd like to make note that I've spent the greater part of this weekend looking here and anywhere else for the pin values for CON1 on the Fusion Gen2 of my Vortex Pro 250 to no avail.

In fact I have only found one thread http://fpvlab.com/forums/showthread....highlight=con1 that refers to CON1 and the question was what type of connector style is used. (jst-zh)

So what I am hoping for is some clarification as to the values of CON1's 4 pins on this board. As I stated above I cannot find anything beyond Immersion's Vortex 250 Pro manual stating available voltages but not which pins at CON1 on page 13:

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As we all know there is no designation in the manual or silk-screened to the Fusion board that denotes which pin is 5 volts, 3.3 volts, ground and signal. Since ImmersionRC has not been forthcoming with any schematics or complete pinout values for the Fusion Gen2 board (That I know of) It looks like
we are left to figure it out ourselves.

So with a 3 cell battery (reading 11.4 volts during testing) connected I have used my DMM to determine voltages and here is what I've discovered.

Lets call pin 1 the pin closest to the edge of the Fusion board and pin 4 furthest from the edge.

Using pin 1 as ground:
Pin 2 reads -3.16 volts
Pin 3 reads 0.00 volts
Pin 4 reads 1.62 volts

Using pin 2 as ground:
Pin 1 reads 3.16 volts
Pin 3 reads 3.28 volts
Pin 4 reads 4.97 volts

Using pin 3 as ground:
Pin 1 reads -0.00 volts
Pin 2 reads -3.28 volts
Pin 4 reads 1.68 volts

Using Pin 4 as ground:
Pin 1 reads -1.63 volts
Pin 2 reads -4.96 volts
Pin 3 reads -1.68 volts

Either I can build or utilize a cable from my bench or I have to buy the Spektrum satellite cable (VXPPMSPK) for $10 that plugs into the PPM port at the rear of the PDB. Rather than that I want to go with Immersionrc's suggestion on page 35 of the Vortex 250 Pro manual and use the included Spektrum cable (which I didn't get with my 2nd hand Vortex).

So I took a look online at the spektrum cable included in Immersionrc's cable kit (BLH9202 $15.99 to $18.99) and was able to see that it goes from 3 pins at the satellite to 4 pins at the Fusion board with one of the pins on the end unused. So it looks as if I may be able to just use a regular satellite cable. Lets find out...

Using the closest to the edge of the Fusion board as pin 1 it goes like this:

Pin 1 signal (grey)
Pin 2 ground (Black)
Pin 3 3.3 volts (Red)
Pin 4 empty

Using this setup with just my regular satellite cable (3 pin to 3 pin) I was able to plug it in as described above and I immediately bound my Spektrum SPM4648 to my DX7s.

If you refer back to my voltage measurements above It appears that it's using pin1 as Signal, Pin 2 as Ground and Pin 3 for 3.3 volts. Once again Pin 4 is unused.

I'm going to stop at this point but I will be continuing with finishing this setup soon. I believe the satellite will be used as a serial device in Betaflight. So I'm off to do some more research and get the Vortex up and flying . . .