NI SCXI 1104 Lowpass filter

I have a NI  SCXI-1104 and in its datasheet says that it has on each channel  a three-pole lowpass filter with a 2 Hz cutoff frequency to reject 60 Hz noise. I need to know: What kind of filter this device uses?  What happen with the data over the cutoff frequency? In my case I need to analyze the frequency between 1 to 8 Hz and reject the others.

This board is for the Excel add-0n called Measure.
Well it's three-pole low pass filter and frequencies above 2 hz are going to be greatly attenuated. This module is intended for thermoucouple (dc) inputs and would not be suitable for any sort of frequency analysis, in my opinion

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    Which module are you using?
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    hello
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    Go to Solution.
    Attachments:
    ssb1.png ‏71 KB

    The realities of real filters!
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  • Lowpass filter in communication

    hello
    i'm using LABVIEW to implement LSB-SSB modulation, this requires a VSB signal passed through a lowpass filter, the problem i couldn't get my required spectrum, i wonder if the problem is in the filter or elsewhere, i hope you can help me in that , i only need to know how the filter in labview works , thanks
    Attachments:
    ssb.png ‏89 KB

    Have you tried the detailed help on the Filter express VI? (Ctrl H --> Detailed help)
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  • How can I filter thermocouple noise using a TC-2095 and SCXI-1102c?

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    Go to Solution.

    Hi RALoo, 
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    National Instruments

  • Scxi 1120 low pass filter specs for anti aliasing

    Hia,
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    90% of all experts aggree that 1 out of 10 experts are wrong

    The specific characteristics of the SCXI-1120 are not available because the filter is not high-performance since it is designed speicifically for noise rejection. From the SCXI-1120 user's manual (http://www.ni.com/pdf/manuals/320425d.pdf), you can see that there are two lowpass filter stages, and then there is also a bandwidth limitation imposed by the amplifiers. The two filter stages are simple RC filters, so I would doubt that the roll-off is steep enough to reach -92dB attenuation at 12.8kHz. I would recommend either designing your own first stage filter, like you had mentioned, or find a way to increase your sample rate.
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  • Is there a low-pass filter that is compatible with the SC-2040?

    I am presently using external anti-aliasing filters with my SC-2040, SSH card. Is there a low-pass filter module that is compatible?

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  • Tried the solutions posted for this "SubVI filter not executable​. Undefined error" but not solving the problem

    Hello,
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    Hi PatanGova,
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  • How to design a stable IIR-Filter for FPGA?

    Hi, I´m new to Labview for FPGA and currently trying to design a lowpass-filter (for a digital mixer, more or less). It should work with a sample-frequency of 200kHz, a passband edge frequency of 3Hz and a stopband edge frequency of 8Hz. An FIR-filter would have a too large order to be implemented, an IIR one seems more practicable. For the design of the filter I'm using the digital filter design toolkit, refering to its manual and the casestudy with analyzing, modeling, simulating and generating a fixed-point filter. Now, I have problems to get a stable filter. While the manual states to adjust the coefficents by trial and error, the designed filter never matches the floating-point reference. Does anyone have experience in creating such filters? Or a hint, how to optimize the coefficient finding process?
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    I have attached the configuration dialog with the settings you specified.
    Message Edited by Christian L on 11-16-2006 09:27 AM
    Christian Loew, CLA
    Principal Systems Engineer, National Instruments
    Please tip your answer providers with kudos.
    Any attached Code is provided As Is. It has not been tested or validated as a product, for use in a deployed application or system,
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    Attachments:
    filterdialog.JPG ‏44 KB

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