+ Post New Thread
Results 1 to 7 of 7
  1. #1
    Newbie level 4
    Points: 676, Level: 5

    Join Date
    Apr 2009
    Posts
    5
    Helped
    0 / 0
    Points
    676
    Level
    5

    how do i measure 2 seperate audio signals on one line?

    I need to measure an audio signal on one line. The only problem is that it has two audio frequencies on the one line one at 2670hz and the other at 1440hz. I obviously cannot just measure it with an o-scope. So my question is there a piece of test equipment that can measure both the audio frequencies? Thank you very much...

    •   AltAdvertisement

        
       

  2. #2
    Full Member level 6
    Points: 5,173, Level: 17

    Join Date
    Feb 2004
    Location
    NE USA
    Posts
    372
    Helped
    74 / 74
    Points
    5,173
    Level
    17

    Re: how do i measure 2 seperate audio signals on one line?

    What measurements are you trying to make? It might be possible to measure these signals with an Oscilloscope.

    Dave
    www.keystoneradio.com



    •   AltAdvertisement

        
       

  3. #3
    Newbie level 4
    Points: 676, Level: 5

    Join Date
    Apr 2009
    Posts
    5
    Helped
    0 / 0
    Points
    676
    Level
    5

    Re: how do i measure 2 seperate audio signals on one line?

    I am trying to verify that the audio signal is infact at the right frequency of 1440hz. The problem with the o-scope is that also on the same line there is also a audio signal of 2670hz on it. So if I tried to verify that the frequency is there i would see on the o-scope alot of distortion because it will be picking up both waveforms mixed together. I need to seperate them somehow or filter out one of the audio freqs. Does anyone know a piece of test equipment that will do that?



    •   AltAdvertisement

        
       

  4. #4
    Advanced Member level 2
    Points: 6,801, Level: 19

    Join Date
    Nov 2004
    Location
    Tamilnadu
    Posts
    659
    Helped
    36 / 36
    Points
    6,801
    Level
    19

    how do i measure 2 seperate audio signals on one line?

    use two separate filter whose cutoff frequencies are as mentioed by you.these can help you to separate the two frequencies..from that point you can measure each audio signals



  5. #5
    Advanced Member level 4
    Points: 7,067, Level: 20
    klystron's Avatar
    Join Date
    Jul 2002
    Location
    South Africa
    Posts
    1,014
    Helped
    192 / 192
    Points
    7,067
    Level
    20

    Re: how do i measure 2 seperate audio signals on one line?

    Use a LM567 tone decoder



  6. #6
    Junior Member level 1
    Points: 1,835, Level: 9

    Join Date
    Nov 2003
    Posts
    16
    Helped
    1 / 1
    Points
    1,835
    Level
    9

    Re: how do i measure 2 seperate audio signals on one line?

    use a spectrum analyzer (expensive javascript:emoticon(''))

    http://www.spectrum-analyzer.info/Sp..._Spectrum.aspx

    Regards



    •   AltAdvertisement

        
       

  7. #7
    Member level 5
    Points: 2,033, Level: 10

    Join Date
    Feb 2005
    Posts
    91
    Helped
    2 / 2
    Points
    2,033
    Level
    10

    how do i measure 2 seperate audio signals on one line?

    Use 2 band-pass filters. Passive ones may work: inductor-capacitor type
    __________________________________________
    low price 1/4W 1% resistors on ebay:
    http://cgi.ebay.com/ws/eBayISAPI.dll...m=300307560505



--[[ ]]--