Mini APM vs APM Pro

[Fr3nzy]

Hi All,

I have a Flying Wings Falcon Evo that I built with a Mini APM FC and MinimOSD, it's worked pretty well other than those wretched JST connectors failing on me. Well I recently had a radio lockout (TBS Crossfire) and the plane did RTL and eventually crashed in a cornfield so at least that part worked. The problem was traced to the radio input connector, I made a new loom but it was still intermittent. Being quite happy with APM and not wanting to spend too much on Pix, I bought an APM Pro from BG, chopped off all the JST's and fitted standard servo plugs and thought that was that. In an attempt to save time, I exported / imported the config (a mistake now I realise) and took it for a test flight.

It flew fine and seamed to work apart from FBW mode wanted to pitch forward and roll left (maybe a level calculation) when I tested RTL, the plane made the initial turn and started to lose altitude but then started to oscillate, within a second, it escalated to a major shake so I aborted the RTL test and flew it back manually (This is probably related to importing the mini APM config, I guess the D term is too high so I've defaulted these back to stock).  The other thing I've noticed is the Artificial Horizon in the OSD is really slow, i'd say it updates at half the speed it used to and cant figure out why, I've increased the SR0 parameters but this doesn't seam to have any effect. I swapped out the APM for another APM Pro and the replacement behaves exactly the same way.

SO i'm wondering if the CPU in the Pro is slower which would explain why the PID's caused oscillations and why the OSD's slow, does anyone have any experience of Mini APM or can shed light on why it appears to run slower?

Thanks for any advise offered.