Hi Jon

    going by your pic ... It seems you have no mass (weight) at the end of=
=20
the arm
and that is why the wire line is slack  also the terminating of that line=20
at the top
end is critical to overcome free swinging problems   follow Geffory's ideas=
=20
using piano wire and turnbuckles and a good pivot point   etc,  as shown in=
=20
the original Lehman design.

  a good mass would be ~ 5 - 10 kg of brass or lead
My commercial horizonal seismo had 10kg brass mass

  without any sort of reasonable mass on the arm   the seismo isnt going to
work   I assume you have something planned  ... altho you havent commented=
=20
on what you are going to use.

cheers
Dave Nelson
Sydney



At 10:19 PM 12/06/2007 +0000, you wrote:
>Hi Chris.
>
>The sensor is 95% done, I hopefully am going to finish it in about two
>weeks time or around that. The arm is 60 cm long. I am using a simple
>wire on the arm, from the top to bottom.
>
>I plan to use the magnet damping system as it is on that webpage you
>pointed to. I just can't set it up at the moment, I am going to get help
>in two weeks time to fix that issue and setup the sensor in a decent
>way. I am also going to fix few bugs that I currently have. But the arm
>goes straigt trugh the holder, it was a mistake that I did when it was
>setup up for me, my mistake. It is going to get that corrected, along
>with few other things.
>
>Regards.
>--
>J=F3n Fr=EDmann
>http://www.jonfr.com
>http://www.simnet.is/jonfr500/earthquake/
>
>__________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email PSN-L-REQUEST@.............. with
>the body of the message (first line only): unsubscribe
>See http://www.seismicnet.com/maillist.html for more information.
>
>
>
>--
>No virus found in this incoming message.
>Checked by AVG Free Edition.
>Version: 7.5.472 / Virus Database: 269.8.15/847 - Release Date: 12/06/2007=
=20
>9:42 PM


__________________________________________________________

Public Seismic Network Mailing List (PSN-L)