Hi Ted,

You need to be sure that a negative voltage is being generated by the
sensor.

One simple way to test the DataQ device is to apply 1.5v, ( dry cell battery
) to the DataQ unit, observe the deflection in Amaseis  then reverse the
polarity and the deflection should be opposite but equal.

 

Regards

Dale

 

  _____  

From: psnlist-request@.............. [mailto:psnlist-request@...............
On Behalf Of Ted Channel
Sent: Thursday, 21 October 2010 11:17 AM
To: psnlist@..............
Subject: Negative clipping in AmaSeis

 

Hi Folks,   I have used DataQ194 ad converters, and 158.   Big price
differences so I use more of the 194.

 

Mostly they work fine.   However from time to time a system will have
negative clipping, nothing below zero, unless you jump close to the machine
and then is shows negative values.

 

We installed a new system, in a school three hours away.    They recorded
their first earthquake, but because of the clipping the data is useless.
It carrys over into Winquake and filtering does nothing to improve it.

 

I had a similar problem, changed the 194, and install a 158 the problem went
away.   Reinstalled the 194, the problem returned.   I wanted to try a new
194, but did not have one.

 

Can anyone help........Have you see something similar?....could it be the
set up procedure in Windata, which comes with the 194.   It has a set up
window for values, and should be set to +10 volts and -10 volts.

 

I don't think it is the sensor.

I don't think it is Amaseis or Winquake.

I don't think it is the computer.

I don't think it is the cables......

 

Thanks, Ted















Hi =
Ted,

You need to be sure that a negative
voltage is being generated by the sensor.

One simple way to test the DataQ =
device is
to apply 1.5v, ( dry cell battery ) to the DataQ unit, observe the =
deflection in
Amaseis  then reverse the polarity and the deflection should be =
opposite
but equal.

 

Regards
=


Dale

 









From:
psnlist-request@.............. [mailto:psnlist-request@............... =
On Behalf Of Ted Channel

Sent: Thursday, 21 =
October 2010
11:17 AM

To: =
psnlist@..............

Subject: Negative =
clipping in
AmaSeis



 



Hi Folks,   I have used DataQ194 ad =
converters,
and 158.   Big price differences so I use more of the =
194.





 





Mostly they work fine.   However from time =
to time
a system will have negative clipping, nothing below zero, unless you =
jump close
to the machine and then is shows negative =
values.





 





We installed a new system, in a school three hours
away.    They recorded their first earthquake, but =
because of
the clipping the data is useless.   It carrys over into =
Winquake and
filtering does nothing to improve it.





 





I had a similar problem, changed the 194, and install =
a 158
the problem went away.   Reinstalled the 194, the problem
returned.   I wanted to try a new 194, but did not have =
one.





 





Can anyone help........Have you see something
similar?....could it be the set up procedure in Windata, which comes =
with the
194.   It has a set up window for values, and should be set to =
+10
volts and -10 volts.





 





I don't think it is the =
sensor.





I don't think it is Amaseis or =
Winquake.





I don't think it is the =
computer.





I don't think it is the =
cables......





 





Thanks, Ted