Hi, I am building a horizontal pendulum sensor, my first attempt.  I =
built my own amp and filter.  I configured the Low pass filter to Low =
pass 2.5Hz.  Before I installed the filter, the sensor would pick up =
footsteps or stomps on the concrete floor, now nothing creates a trace, =
except If I blow on the beam it develops a nice trace.   No earthquakes =
since I installed the filter so I don't know if its going to work.

 1 I could use some advise, if the amp and filter seem to be okay or if =
I have over done something.

2  Another issue is, I am overwhelmed with confusion about "Seconds vs =
Hz"  I understand how to work with them and what they mean.  But the =
more I read the more confused I get.  The events come in low =
frequencies, 10 to 20seconds  is that  0.1Hz. and .05Hz?   Does that =
make everything above those Hz, or should I say, below those  periods =
unwanted?   You can see I need help.

3  Using AmaSies, what values do I set the Low pass filter, and what =
values do I set the high pass filter, for enhancing an enlarged detail =
trace?  Do I use both a low and high together.........Some examples =
would be helpful.   The little I have use them has just been trial and =
error, to get the best picture.

Many thank, Ted







Hi, I am building a horizontal pendulum =
sensor, my=20
first attempt.  I built my own amp and filter.  I configured =
the Low=20
pass filter to Low pass 2.5Hz.  Before I installed the filter, the =
sensor=20
would pick up footsteps or stomps on the concrete floor, now nothing =
creates=20
a trace, except If I blow on the beam =
it develops=20
a nice trace.   No earthquakes since I installed the filter so =
I don't=20
know if its going to work.
 
 1 I could use some advise, if the =
amp and=20
filter seem to be okay or if I have over done something.
 
2  Another issue is, I am =
overwhelmed with=20
confusion about "Seconds vs Hz"  I understand how to work with them =
and=20
what they mean.  But the more I =
read the=20
more confused I get.  The events come in low frequencies, 10 to=20
20seconds  is that  0.1Hz. and .05Hz?   Does that =
make=20
everything above those Hz, or should I say, below those  periods=20
unwanted?   You can see I need help.
 
3  Using AmaSies, what values do I =
set the Low=20
pass filter, and what values do I set the high pass filter, for =
enhancing an=20
enlarged detail trace?  Do I use both a low and high =
together.........Some=20
examples would be helpful.   The little I have use them has =
just been=20
trial and error, to get the best picture.
 
Many thank, Ted