Expert: William J Perkins - 10/21/2008

Question
I am trying to reset the night cam so that the clock doesn't chime at night. It's supposed to go off at 11pm until 7am, but it goes off at 9.45pm and comes back on at 7am. I have moved the cam wheel round, but this hasn't changed anything.

Answer
Not only is the cam involved but so is gear ratio.  Not knowing the history of the clock I cannot give a meaningful response.  I can tell you, however, that if at one time the clock did function as represented, the problem could not be with the cam, it would be a ratio proeblem.  If, on the other hand, the clock never functioned as advertised the problem would be with the cam, i.e., the wrong cam in the right place.  The cam, as you know is a fixed piece of metal, the distance between its high point and low point is fixed, so no matter what position it is in the same number of hours have to pass between engagment with the gear train and the disengagment.  If this is the problem you replace the cam.  Should the problem be with ratio the correction would rest with altering the lift lever or the engagement gear, or both.  In summation I can't see the problem so I can only generalize.  Regards WJP