In a message dated 2007/03/31, tchannel@.............. writes:

> Hi All, Looking closely at the board I see two resistors which are "Open" 
> "cracked"
> Its a wonder it works at all, but some parts of it do work. Channel 1, only 
> puts out + voltage, just a small amount of -
> I think that account for the AmaSeis trace showing only the top part of an 
> earthquake.

Hi Ted,

       The input resistors are two 200 K in series. The offset line is 100 K 
to the centre point. If any of them are damaged, it should not be difficult to 
replace them. Alternatively, could you  unsolder the resistors on CH4 and 
replace the ones on CH1? The resistor values are printed on them eg 2003.
       I get about -0.59 V on the offset line and about 90 mV on the input. I 
suspect that this is because the ADC is not in operating mode. The offset 
line should be -5V for +/-10V input. Check the voltage on the offset line while 
the channel is switched on?

> However Channel, 2,3,4 all seem to work showing both positive and negative 
> movement "In DataQ Software Only", in this software Channel 1, only shows 
> positive trace movement, and, no negative.

       You could get this with failed resistors. Is the range 5V or 10V? I 
suspect that the ADC may have been 'modified' for a single polarity 5V signal? 
Can the friend who gave it to you provide any information? 

> When I connected my Sensor to Channel 2,3 or 4 Using DataQ,  I was thinking 
> it would then work in AmaSeis, but it does not.  It looks as if AmaSeis will 
> not read any Channel except Channel 1. Even though in DataQ Channel 2,3,4 
> all seem to work fine.  If I connect the sensor to Channel 3,  AmaSeis shows a 
> trace, but the trace does not move in either direction if I stimulate the 
> sensor.  This is true for Channel, 2,3,4.  Only Channel 1, moves the trace in 
> AmaSeis.
> I think you can change the com port, in AmaSeis, but is there anywhere you 
> can or need to change for Channel selection?
> In DataQ I closed all the Channels except Ch. 3 and saved before closing.  
> So If I were just using DataQ software, I would be operational.

       Amaseis normally uses CH1 only. However there are two setup files 
Amaseis.ini and AS1.ini. It may be possible to set a different channel by editing 
and then saving the file, but I am not sure. I know that you get your 
different sample rates this way. If you use a Dataq and Amaseis without editing the 
ini file, you just get 6 SPS.

       This information is taken from an old 8 bit DI-194 board, which I 
suspect that you have.

       Regards,

       Chris Chapman   
In a me=
ssage dated 2007/03/31, tchannel@.............. writes:



Hi All, Looking closely at the=20=
board I see two resistors which are "Open" "cracked"

Its a wonder it works at all, but some parts of it do work. Channel 1, only=
 puts out + voltage, just a small amount of -

I think that account for the AmaSeis trace showing only the top part of an=20=
earthquake.




Hi Ted,



       The input resistors are two 200 K in se=
ries. The offset line is 100 K to the centre point. If any of them are damag=
ed, it should not be difficult to replace them. Alternatively, could you&nbs=
p; unsolder the resistors on CH4 and replace the ones on CH1? The resistor v=
alues are printed on them eg 2003.

       I get about -0.59 V on the offset line=20=
and about 90 mV on the input. I suspect that this is because the ADC is not=20=
in operating mode. The offset line should be -5V for +/-10V input. Check the=
 voltage on the offset line while the channel is switched on?



However Channel, 2,3,4 all see=
m to work showing both positive and negative movement "In DataQ Software Onl=
y", in this software Channel 1, only shows positive trace movement, and, no=20=
negative.




       You could get this with failed resisto=
rs. Is the range 5V or 10V? I suspect that the ADC may have been 'modified'=20=
for a single polarity 5V signal? Can the friend who gave it to you provide a=
ny information? 



When I connected my Sensor to=20=
Channel 2,3 or 4 Using DataQ,  I was thinking it would then work in Ama=
Seis, but it does not.  It looks as if AmaSeis will not read any Channe=
l except Channel 1. Even though in DataQ Channel 2,3,4 all seem to work fine=
..  If I connect the sensor to Channel 3,  AmaSeis shows a trace, b=
ut the trace does not move in either direction if I stimulate the sensor.&nb=
sp; This is true for Channel, 2,3,4.  Only Channel 1, moves the trace i=
n AmaSeis.

I think you can change the com port, in AmaSeis, but is there anywhere you=20=
can or need to change for Channel selection?

In DataQ I closed all the Channels except Ch. 3 and saved before closing.&n=
bsp; So If I were just using DataQ software, I would be operational.<=
FONT  COLOR=3D"#000000" BACK=3D"#ffffff" style=3D"BACKGROUND-COLOR: #ffffff"=
 SIZE=3D3 PTSIZE=3D12 FAMILY=3D"SANSSERIF" FACE=3D"Arial" LANG=3D"0">



       Amaseis normally uses CH1 only. However=
 there are two setup files Amaseis.ini and AS1.ini. It may be possible to se=
t a different channel by editing and then saving the file, but I am not sure=
.. I know that you get your different sample rates this way. If you use a Dat=
aq and Amaseis without editing the ini file, you just get 6 SPS.



       This information is taken from an old 8=
 bit DI-194 board, which I suspect that you have.



       Regards,



       Chris Chapman