That's a good catch. A-9746 should be around 1.5 ohms. If it's really reading less than .5 ohm, then yes you need a new coil.

- TimMe

It sounds like the Q relay may be sticking. Be sure the face of the relay armature (the part that contacts the coil core) is clean and smooth, and also check the switches on the relay for adjustment or binding issues.

- TimMe

I looked at the video, and your score motor seems to be fine. Also I noticed that your chime unit sounded a nice clean five times in both cases where you said you were scoring more than 500. So I would focus on the score unit itself. It sounds like the score unit may be skipping digits when it steps.

You could have an electrical issue, which would be the switch on the M relay that supplies power to the 100s score unit drive coil. Check the switches on the M relay, and clean and adjust the two switches with the large contact points - one is for the chime unit (which sounds like it's working correctly) and the other is for the score unit drive coil.

Once you've confirmed the M relay switches are OK, then the most likely issue is a mechanical stepping problem with the 100s score unit. You can actuate the M relay by hand while you watch the score unit. If the score unit jumps more than one digit each time it steps, then you very likely have a mechanical problem. The most common reason that these score units jump multiple digits when stepping is either because the anti-back-turn ratchet finger is bent and is no longer keeping the reel from moving backward, or the score unit was assembled with the nylon drive gear for the reel engaged to the wrong tooth of the drive rack.

- TimMe