In a message dated 11/8/02 10:23:32 PM GMT Standard Time, fxc@....... writes:


>  I think John may have solved both problems with a
> cheap (but not cheaply made) base for amateur seismologists.  Also his
> method of using ball bearings at the pivot point and suspension point are
> outstanding. (John pioneered the ball bearing method). Feedback is welcome.

Hi PSN,

Could someone please comment on how John Cole's use of a ball bearing at the 
top suspension point is an advantage? Does this not introduce friction where 
there wasn't any before? 

Thanks, 
Cap
In a message dated 11/8/02 10:23:32 PM GMT Standard Time, fxc@....... writes:





 I think John may have solved both problems with a

cheap (but not cheaply made) base for amateur seismologists.  Also his

method of using ball bearings at the pivot point and suspension point are

outstanding. (John pioneered the ball bearing method). Feedback is welcome.




Hi PSN,



Could someone please comment on how John Cole's use of a ball bearing at the top suspension point is an advantage? Does this not introduce friction where there wasn't any before? 



Thanks, 

Cap