I see your post is edited to note you want to use a single radio with the A2. In that case I would not use a second receiver. Just link your 14SG to the A2 and map the channels in the assistant software. The typical setup requires 7 channels for flight control, 1 channel for gear, and 4 channels for the gimbal (using the F1-F4 aka D1-D4 ports on the A2). It's very easy to do using the channel mapping in the A2 assistant software.
Wow that is what I wanted and wished. I m just setting up the S900 tomorrow I will do the A2 setup. Thanks alot. I will have a good sleep tonigth :nevreness: