OK...12" sounded a tard too small:
Here is a good reading about the gain settings: (It's about the Naza, but counts for the WooKong as well...you got a WooKong on the S800, right ?)
http://www.rcgroups.com/forums/showthread.php?t=1796013
Some people treat the gain-setting like the holy grail, others couldn't care less.....both fly. I always start with about 130 each, and than crank it step by step all the way up untill it starts shaking....then down about 10 - 15 points. The new Bluetooth-LED helps a lot.
the CG has been determined for the GPS antenna ( although I have been using a mixture of two 5000 maH batteries in series and a single 8.5 maH six six cell battery )
The Center of Gravity for the GPS is not really that important (some people just set the Z-axis if it is sitting on a pole ( values will be negative). More important is the COG in relation to the position of the IMU. That vid explains it pretty good:
These green and red (+ / - ) settings can be very irritating, just make sure you get that right.
If you change any COG settings, just re-calibrate your Transmitter stick settings in the Assistant software, and after that re-calibrate the compass.....just to be sure
One thing I did if I could not get rid of a slight drifting was just to either move the center point of the stick on my transmitter (depends on the model of transmitter you have) just slightly to the opposite direction of the drift, or just played a little with the trim button / slider.
A few people will start to scream and shout at this point, but if you don't over-do it, it doesn't do any harm as long as the values don't change too much.
Chris
