Timex Indiglo WR 30M
to turn off hourly chime on the times wr 30m, simply press (in any mode, i just use the regular clock mode) the start/stop button (top right hand button) once (for about half a second).
if you don't hear anything, you've turned off the hourly chime! if you hear two short beeps, you've turned on the hourly chime. turning the chime off/on is cyclic. if you press once and hear nothing, it's off. if you press again, you'll hear two beeps and the hourly chime is now on. a lot of times that button hits my wrist (i wear it on my left hand) by accident, and that's how the chime turns on and off. i hope this helps someone.