tascam 388 question (for a reel person?)

[triple]

hey,
i fired up my 388 this weekend and noticed that right when i turned it on a little silver piece (i don't know what it's called) down on the right side of the headstock was spinning...does this little piece always spin when the machine is on...even when nothing was in play or record mode this little thing was always turning...i never noticed this before and thought that maybe something was broken or that it was always spinning and i just never noticed it...i don't know what the part is called...i looked in the manual for it but couldn't find it...it's right down off of the headstack, almost touching it, on the right side...it doesn't seem to touch the tape at all...any suggestions????
thanks

 

[Beck]

You're fine. That's the capstan and it always spins. When you press play the tape is pulled between that and the rubber pinch roller.

The capstan is attached to a weighted spinning flywheel below, which must be up to speed when play or record is engaged. The capstan and pinch roller function together to maintain the steady tape speed.

Tim