Thank You Chris for the =E2=80=98drumplot=E2=80=99 advice. One thing I =
saw immediately with this new display is the (I assume) auto traffic =
noise. It is relatively quiet from about 11PM to 6Am local time, after =
that the background noise builds up. I should add that the resonant =
period is about 23 seconds and I=E2=80=99m using the Chapman magnet and =
sensor coil design.
Thank you,
Gary
=20
=20
=20
=20
=20
From: psn-l-request@.............. [mailto:psn-l-request@............... =
On Behalf Of ChrisAtUpw@.......
Sent: Tuesday, July 08, 2008 7:52 PM
To: psn-l@..............
Subject: Re: The Lehman is Up and Running
=20
In a message dated 2008/07/09, gel@................. writes:
I connected my first Lehman to the electronics last night and receiving =
data. It looks just like a seismograph should.=20
Hi Gary,
Well done!
Now the next question is: what is the best method to adjust the gain of =
the=20
amplifier-A/D converter (I have Larry=E2=80=99s boards). Do I wait to =
receive some substantial events and then make adjustments.=20
I set the gain initially so that the ocean microseisms are about =
100 / 200 counts in 'quiet' conditions. You may want to record quakes =
which have 1/10 the amplitude of the background.
Also, is there any consensus (probably not) on desired format for the =
seismometer=20
display. I=E2=80=99m using 4 traces of 10 minutes each at this time.
Most folks use a 24 line x 1 hr 'drumplot' display. You can view =
the last 24 hrs activity at a glance and then extract any section which =
has an earthquake on it for further analysis. You can also set display =
filters to ignore the microseism background.
Regards,
Chris Chapman=20
Thank You Chris for the =E2=80=98drumplot=E2=80=99 =
advice. One thing I saw
immediately with this new display is the (I assume) auto traffic noise. =
It is
relatively quiet from about 11PM to 6Am local time, after that the =
background
noise builds up. I should add that the resonant period is about 23 =
seconds and
I=E2=80=99m using the Chapman magnet and sensor coil =
design.
Thank you,
Gary
From:=
psn-l-request@.............. [mailto:psn-l-request@............... On =
Behalf
Of ChrisAtUpw@.......
Sent: Tuesday, July 08, 2008 7:52 PM
To: psn-l@..............
Subject: Re: The Lehman is Up and Running
In
a message dated 2008/07/09, gel@................. writes:
I
connected my first Lehman to the electronics last night and receiving =
data. It
looks just like a seismograph should.
Hi Gary,
Well done!
Now the next question is: what is the best method to adjust the gain of =
the
amplifier-A/D converter (I have =
Larry=E2=80=99s boards).
Do I wait to receive some substantial events and then make adjustments. =
I set the gain initially so that =
the ocean
microseisms are about 100 / 200 counts in 'quiet' conditions. You may =
want to
record quakes which have 1/10 the amplitude of the background.
Also, is there any consensus (probably not) on desired format for the
seismometer
display. I=E2=80=99m using 4 traces of 10 =
minutes each at
this time.
Most folks use a 24 line x 1 hr =
'drumplot'
display. You can view the last 24 hrs activity at a glance and then =
extract any
section which has an earthquake on it for further analysis. You can also =
set
display filters to ignore the microseism background.
Regards,
Chris Chapman