As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAKEOFF ROLL, WHILE ADVANCE POWER FOR TAKEOFF, NR2 PROP RPM DROPPED TO 500 RPMS AND CONTINUE TO DROP. REPLACED NR 100 TSCU CONTROLLER AND SECURED, OPS CHECKED ACFT IAW -8 MAINT. OPERATING MANUAL. REFERRING TO COMPONENT CHANGE OUT. OPS CHECKED GOOD ON THE GROUND.