In a message dated 2008/06/11, jamesridout@.............. writes:

> And as far as I can see The ideal amount is 0.7 - 0.8 and that means that 
> if I walk up to the seismograph and the pen deflects 10mm, then the pen should 
> return 0.5mm in the opposite direction then back to zero. Is it me, or does 
> this seem like too much.

Hi James,

       I draw a thin black line on a sticky label and mount it vertical on 
the end of the mass.
       Over the top of this, separated by maybe 1/16", I mount a clear 
plastic ruler.
       I use a x2.5 mounted magnifying glass to view the ruler and the 
vertical line.
       I move the ruler so that the line is on a cm ruler mark.
       I use a rod or ruler as a lever resting on the baseplate to slowly 
move the mass 10 mm to one side.
       I remove the lever and watch what happens to the mass line.
       It should go past the rest postion by ~0.5 mm and then return to the 
rest postion. 
       The magnifying glass makes this fairly easy to observe.

       Regards,

       Chris Chapman   
In a me=
ssage dated 2008/06/11, jamesridout@.............. writes:



And as far as I can see The ide=
al amount is 0.7 - 0.8 and that means that if I walk up to the seismograph a=
nd the pen deflects 10mm, then the pen should return 0.5mm in the opposite d=
irection then back to zero. Is it me, or does this seem like too much.



Hi James,



       I draw a thin black line on a sticky la=
bel and mount it vertical on the end of the mass.

       Over the top of this, separated by mayb=
e 1/16", I mount a clear plastic ruler.

       I use a x2.5 mounted magnifying glass t=
o view the ruler and the vertical line.

       I move the ruler so that the line is on=
 a cm ruler mark.

       I use a rod or ruler as a lever resting=
 on the baseplate to slowly move the mass 10 mm to one side.

       I remove the lever and watch what happe=
ns to the mass line.

       It should go past the rest postion by ~=
0.5 mm and then return to the rest postion. 

       The magnifying glass makes this fairly=20=
easy to observe.



       Regards,



       Chris Chapman