Hi Rudy,  On these questions you will get a lot of help.   I too started =
in my garage, here is what I found.

1.  I first just built the sensor and got it up and running, with no =
cover at all.   It worked fine but the air currents I made, as I walked =
by, created large spikes, noise.  Just pointing out the obvious these =
sensors are very very sensitive  to air movement. =20

2.  The next thing I noticed was each morning or night, with no air =
movement in the garage, the background noise changed dramatically, as it =
was still uncovered.   The cause was the cold concrete flood was cooler =
than the air, and caused small undetected air currents, rising up.   =
This was seen on the screen as night time vs. day time differences in =
large background noises.  This was all new to me as this was my first  =
involvement.   Both of these problems were corrected by enclosing the =
sensor in a box.   Much has been written about the best way to build an =
enclosure.  I tried different enclosures and found all of them to be =
improvements.  I tried an inverted fish aquarium.  I tried a wood frame =
covered with blankets.  I tried Styrofoam box.  I tried Plexiglas box.  =
I tried insulated and uninsulated.   I tried sealing the box to the =
floor and unsealed.
Even a simple cardboard box.   These all worked, some better than =
others.   However after correcting these issues, most of my unwanted =
noise came from the Daytime city activities.   It would start at 7:00am =
and end at 5:00pm.   Things would always quiet down at night, with =
little background noise.

3.  Another observation about my garage floor.  It is made of several =
divided sections or slabs.   I thought these large sections of concrete =
were solid.  But to the sensor they were as flexible as thin plywood.  =
If you moved from one section to another the sensor would pick it up as =
if you were moving from one teeter totter to another.   This did not =
stop me from using this concrete floor.   I just realized you could not =
walk around in the garage without creating noise.

I used the garage for many months.   It was handy and after I realized =
the sensor needed an enclosure and I could not walk around out there it =
worked fine for me.   For some people the garage may be the only place =
they have and it worked for me.

Ted
  ----- Original Message -----=20
  From: Rudy Norvelle=20
  To: psn-l@.................
  Sent: Saturday, August 30, 2008 6:09 PM
  Subject: Question on seting up a seismograph


  I am a long time lurker on this list and am finally getting around to =
setting up my seismograph, however the only place I will have available =
to set it up will be in my garage.  I know that this will not be the =
most advantageous place to do so.  Has anyone set one up in their garage =
and what would be the best way of isolating the seismograph from some of =
the noise?  I know I will have a fair amount of background noise and was =
hoping that I can isolate it so that I can get  meaningful event =
recordings.  I am at this time leaning toward a Lehman type sensor with =
Larry's Hardware.  Any help or directions to websites would be =
appreciated.

  thanks,








Hi Rudy,  On these questions you =
will get a=20
lot of help.   I too started in my garage, here is what I=20
found.
 
1.  I first just built the sensor =
and got it=20
up and running, with no cover at all.   It worked fine but the =
air=20
currents I made, as I walked by, created large spikes, noise.  Just =

pointing out the obvious these sensors are very very =
sensitive =20
to air movement.  
 
2.  The next thing I noticed was =
each morning=20
or night, with no air movement in the garage, the background noise =
changed=20
dramatically, as it was still uncovered.   The cause was the =
cold=20
concrete flood was cooler than the air, and caused small undetected air=20
currents, rising up.   This was seen on the screen as night =
time vs.=20
day time differences in large background noises.  This was all new =
to me as=20
this was my first  involvement.   Both of these problems =
were=20
corrected by enclosing the sensor in a box.   Much has been =
written=20
about the best way to build an enclosure.  I tried different =
enclosures and=20
found all of them to be improvements.  I tried an inverted fish=20
aquarium.  I tried a wood frame covered with blankets.  I =
tried=20
Styrofoam box.  I tried Plexiglas box.  I tried insulated and=20
uninsulated.   I tried sealing the box to the floor and=20
unsealed.
Even a simple cardboard =
box.   These all=20
worked, some better than others.   However after correcting =
these=20
issues, most of my unwanted noise came from the Daytime city=20
activities.   It would start at 7:00am and end at =
5:00pm.  =20
Things would always quiet down at night, with little background=20
noise.
 
3.  Another observation about my =
garage=20
floor.  It is made of several divided sections or =
slabs.   I=20
thought these large sections of concrete were solid.  But to the =
sensor=20
they were as flexible as thin plywood.  If you moved from one =
section to=20
another the sensor would pick it up as if you were moving from one =
teeter totter=20
to another.   This did not stop me from using this concrete=20
floor.   I just realized you could not walk around in the =
garage=20
without creating noise.
 
I used the garage for many =
months.   It=20
was handy and after I realized the sensor needed an enclosure and I =
could not=20
walk around out there it worked fine for me.   For some people =
the=20
garage may be the only place they have and it worked for =
me.
 
Ted

  
----- Original Message ----- 
  From:=20
  Rudy Norvelle 
  
To: psn-l@.............. 
  
Sent: Saturday, August 30, 2008 =
6:09=20
  PM
  
Subject: Question on seting up =
a=20
  seismograph
  


  
I am a long time lurker on this =
list and=20
  am finally getting around to setting up my seismograph, however the =
only place=20
  I will have available to set it up will be in my garage.  I know =
that=20
  this will not be the most advantageous place to do so.  Has =
anyone set=20
  one up in their garage and what would be the best way of isolating the =

  seismograph from some of the noise?  I know I will have a fair =
amount of=20
  background noise and was hoping that I can isolate it so that I can =
get =20
  meaningful event recordings.  I am at this time leaning toward a =
Lehman=20
  type sensor with Larry's Hardware.  Any help or directions to =
websites=20
  would be appreciated.
  
 
  
thanks,
  
 
  
Rudy=20
Norvelle