"I found this on U-blox site 
GPS Antennad RF Design considerations for u-blox receivers - application note
http://www.u-blox.com/images/downloads/Product_Docs/GPS_Antennas_Ap...

maybe useful to people that plan to change the ground plane"

"@Damain
got this answer from Randy 5-6 weeks ago http://diydrones.com/xn/detail/705844:Comment:1800261
The high peak in load starts when code get a gps fix or amount sat (or both)

i have no spare time to investigate it, to busy at work."

"Copy&paste error from AP_NavEKF.h  to    AP_NavEKF.cpp

Git search 'AP_Float _gpsNEVelVarAccScale'"

"https://github.com/diydrones/ardupilot/blob/master/ArduCopter/Relea..."

"hi Randy

The top value is >25000, low value : 270 - 439 and this is divide by 10 ??
@param load Maximum usage in percent of the mainloop time, (0%: 0, 100%: 1000) should be always below 1000…"

"video link FIX"

"CPU load going crazy >2500%   in mission planner and APM planner.
with firmware 3.2rc10 and 3.2rc11, if i disconnect GPS it goes down to around 15-20%
video on bench
Hardware : Pixhawk and 3DR GPS v2 nothing else connected

dataflash from outside…"

"Got the same result without Mission Planner"

"I use Mission Planner 1.3.10 Build 1.1.5369.11976"

"Telemetry is logging twice, not all the time , do we need that much logging
Sort on RAD2014-08-30 08-25-31.bin"

"Hi Randy
a little info:
px4firmware in AC3,2-rc10 release  is 23a11fc NOT the latest,

BTW: Great work"

"Use Pixhawk External LED http://store.3drobotics.com/products/pixhawk-peripheral-kit
The internal LED will be OFF, no heat & light inside pixhawk case"

"Nice work Randy

It would be nice to have last update date on each page (maybe also created date).

With this dates , editors and readers can see wish page that has old info and need a update."

"Scroll down bottom of page
http://store.3drobotics.com/products/apm-2-6-kit-1"

"Only for Pixhawk board
https://github.com/diydrones/ardupilot/pull/1266"