How to measure slow ramp in scope

Discussion in 'General Electronics Chat' started by nepdeep, Jan 19, 2013.

  1. nepdeep

    Thread Starter Member

    Sep 14, 2011
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    Hi,
    I have a NTC resistor whose resistance decreases upon increasing the temperature. Now I want to measure the voltage at the voltage division between NTC and the resistor. The voltage also decreases as the temperature increases...
    The thing is...the temperature increases slowly...
    so the voltage would decrease slowly....
    how can i measure or see this in the oscilloscope...
     
  2. MrChips

    Moderator

    Oct 2, 2009
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    Use a DVM.
     
  3. nepdeep

    Thread Starter Member

    Sep 14, 2011
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    Mr.chips I looked upon some stuffs called Digital Video Measurement...but still...I want to know if I can do that in my normal analog scope...is it possible to see slowly ramping dc voltage...
     
  4. MrChips

    Moderator

    Oct 2, 2009
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    DVM stands for digital voltmeter.
     
  5. t06afre

    AAC Fanatic!

    May 11, 2009
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    Is this part of some datalogging project? Some DVM allow connection to a PC. For slow changing signals like temperature this may work
     
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  6. nepdeep

    Thread Starter Member

    Sep 14, 2011
    139
    0
    I have made a simple temp sensor...that shuts down the circuit when the temperature is above certain degree..but the temperature rise is gradual and slow..so i need to keep track of temperature from the beginning and see when it is enabled during the ramp...then i can verify my design....that it works...
     
  7. bertus

    Administrator

    Apr 5, 2008
    15,648
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    Hello,

    If the scope has two channels, put both on DC measurement on the same scale.
    Ground both channels and put the lines on the same level.
    Put one channel on the reference.
    Put the other on the measured signal.
    If the comparator inputs are equal, the lines will cross.

    This will not be as accurate as measurements with a Digital Volt Meter as suggested by MrChips.

    Bertus
     
    Last edited: Jan 19, 2013
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