Hello -After a too long repair issue with my elevation rotor I want to share this information. The position potentiometer went bad in my rotor. I got a new pot from Yaesu. The current replaceable part is not the same as the original. There is a small alignment key way in the original pot that makes for proper alignment. The replacement pot has the same alignment "bump" but the pot is physically different is size therefore the alignment does not line up. The small key way has to be ground off so this makes proper alignment both physically and electrically critical. There are internal stops in the pot which would make improper alignment to cause stripped gears. This is all doable but requires very close attention to detail. Short of this you can always just send the rotor to Yaesu. This was real PITA job. 73 Bob W7LRD Seattle