Please help with weird motor encoder signal

[ZAHN]

Attached is is the signal that is comming out of the motor encoder. The first image is at slow speed showing square waves with what appears to be sine waves inside? However at full speed the signal gets garbled. Anyone know how to fix it? Any insight would be greatly appreciated!

[Tom45]

Those traces look like they might be composites due to triggering difficulties.

Try setting the sweep rate to 20 or 50 usec/div and then use single sweep to capture just one trace and then stop.