HomeMade Quad "Pulsing" Issues

[brettwal]

Built a homemade quad out of 5/8" poplar and hobby ply. It's an 850. Running one of the $69 Mega boards with a Free IMU .35 BMP. 10x4.5 props(balanced) on SK 3530 1100Kv motors. FC is very well isolated and there are only the slighest of vibrations. Running MW 2.1 with default PIDs. RCTimer 30A's flashed with SimonK code & calibrated. Does the same in Gyro Mode or Acc mode. It will hover and it is a stable hover....Except: If I don't stay on the throttle, it pulses, severly. It will pulse it's way into a low Earth orbit if I let it. I also seems to "Spaz out" every once and a while too. That is it seems to jerk about suddenly but, only for a brief period and only small movements. You would think Vibrations! but no. I even tried enabling progressivly lower filters but it did not help. Lowered PIDs too, no change. Any ideas? This is the first time I have used this FC, I'm going to slap a know good Crius SE on it just to make sure the frame is not the cause.

[carter]

I have "Seen" this behavior before. COULD be a frame issue.

[crashlander]

Hello,
I had same issues with homemade shield for Mega2560 + ATAVRSBIN1 but changing to Crius SE fixed everything.

[brettwal]

Well, tried A Crius SE and it made no noticable improvement. Had 2 other incidents where the quad just sort of did its own thing regardless of my control inputs. The 2nd incident was fatal. Electronics now live on a homemade H quad and seem to perform much better. Perhaps the frame was the cause but, I will never know.