The number of possible seismic instrument configurations which will =
provide some response  to seismic motions is vast. The question is the =
practicality/utility of a given configuration.

The key figure of merit for any instrument configuration  is the =
instrument self noise and response as a function of frequency. This =
directly determines the minimum seismic motion the instrument is capable =
of detecting and then providing useful data for analysis.

If one is willing to wait for that rare magnitude 7 or 8 event the =
simplest / noisiest instrument may do the job in some contexts, such as =
classroom demonstrations .=20

The amateur astronomer community has evolved to the point where it =
provides useful  ( if not essential)  information to the astronomy =
scientific community. I believe the amateur seismology community could =
do a similar service but not with inadequate instrumentation.=20

 The goal should be to develop amateur instruments with characteristics =
near the performance of professional instruments and then operating  =
them in reasonably low noise sites. (An instrument in a residential =
basement  will work reassembly well if carefully done.)=20

Larry Cochrane has  already provided us with  excellent equipment to =
handle the sensor data and connect it to a network. Some work needs to =
be done in this area but we have a good start.

My challenge is to include instrument self noise and generator constant, =
both as a function of frequency, as a FIRST PRIORITY when evaluating  =
the utility of an instrument concept.=20

Just another gadget that will respond if you shake it is not where we =
want to spend our efforts and resources.

I do  NOT  mean to imply there are not some truly innovative and =
possibly revolutionary ideas out there but we should  look at each of =
them  carefully to determine early whether they justify significant =
effort or belong in the "that was interesting" stack. =20

Just where determination is made is a personal choice but it should be =
based on some form of analysis and/or test.

Comments Please.=20

Dave Nelson
Rolling Hills Estates, California







 

The number of =
possible seismic=20
instrument configurations which will provide some response  to =
seismic=20
motions is vast. The question is the practicality/utility of a given=20
configuration.
 
The key figure of =
merit for=20
any instrument configuration  is the instrument self noise and =
response as=20
a function of frequency. This directly determines the minimum seismic =
motion the=20
instrument is capable of detecting and then providing useful data for=20
analysis.
 
If one is willing to =
wait for=20
that rare magnitude 7 or 8 event the simplest / noisiest instrument may =
do the=20
job in some contexts, such as classroom demonstrations .=20
 
The amateur =
astronomer community=20
has evolved to the point where it provides useful  ( if not=20
essential)  information to the astronomy scientific community. I =
believe=20
the amateur seismology community could do a similar service but not with =

inadequate instrumentation. 
 
 The goal =
should be to=20
develop amateur instruments with characteristics near the performance of professional instruments and then =
operating  them=20
in reasonably low noise sites. (An instrument in a residential basement=20
 will work reassembly well if carefully done.) 
 
Larry Cochrane has=20
 already provided us with  excellent equipment to =
handle the=20
sensor data and connect it to a network. Some work needs to be done in =
this area=20
but we have a good start.
 
My=20
challenge is to include instrument self noise and generator constant, =
both as a=20
function of frequency, as a FIRST PRIORITY when evaluating  the =
utility of=20
an instrument concept. 
 
Just another gadget =
that will=20
respond if you shake it is not where we want to spend our efforts =
and=20
resources.
 
I do =
 NOT  mean=20
to imply there are not some truly innovative and possibly =
revolutionary=20
ideas out there but we should  look at each of them  carefully =
to=20
determine early whether they justify significant effort or belong in the =
"that=20
was interesting" stack.  
 
Just where =
determination is=20
made is a personal choice but it should be based on some form of =
analysis=20
and/or test.
 
Comments Please. =

 
Dave =
Nelson
Rolling Hills =
Estates,=20
California