PSN-L Email List Message

Subject: Re: Long Frequency noise?
From: chrisatupw@.......
Date: Thu, 24 Dec 2009 08:51:50 EST


 
In a message dated 24/12/2009, tchannel@............ writes:

Hi Folks,  I just recorded the 6.3M  Primor'ye Russia,  on three sensors, a 
Lehman, a Vertical and a new horz  I call ch 2.
 
The Ch 2 sensor is new, and has a period of 22  second, horz pendulum like 
a Lehman.   This new sensor has always  had (long period noise)?  FFT...... 
This was the first earthquake I  have received since I installed it.   I 
normally filter 1 for low  pass, .05 for high pass................This time I 
had to use 1 for low pass  and .5 for high pass, to clean it up.
 
I can send all three .psn files, all unfiltered,  if you think you can tell 
me what is causing the  noise. 



Hi Ted,
 
    I will have a look if you like. What is the  construction of Ch 2, 
please? 
 
    Regards,
 
    Chris Chapman





In a message dated 24/12/2009, tchannel@............ writes:
Hi Folks,  I just recorded the 6.3= M=20 Primor'ye Russia,  on three sensors, a Lehman, a Vertical and a new= horz=20 I call ch 2.
 
The Ch 2 sensor is new, and has a perio= d of 22=20 second, horz pendulum like a Lehman.   This new sensor has alw= ays=20 had (long period noise)?  FFT...... This was the first earthqu= ake I=20 have received since I installed it.   I normally filter 1 for= low=20 pass, .05 for high pass................This time I had to use 1 for low= pass=20 and .5 for high pass, to clean it up.
 
I can send all three .psn files, all un= filtered,=20 if you think you can tell me what is causing the=20 noise. 
Hi Ted,
 
    I will have a look if you like. What is the= =20 construction of Ch 2, please?
 
    Regards,
 
    Chris Chapman

[ Top ] [ Back ] [ Home Page ]