Help on loop back cable?

Discussion in 'General Electronics Chat' started by DIYSteve, Aug 21, 2012.

  1. DIYSteve

    Thread Starter New Member

    Oct 27, 2011
    24
    0
    I've been using the free oscilloscope program Visual Analyzer (VA). Available here:

    http://www.sillanumsoft.org/prod01.htm

    I used to be able to play a video and analyze the audio track with the VA. This was helpful as a tachometer for motor experiments. That was with my old laptop.

    I have a new laptop, now and I cannot find a way to connect the audio out via settings to the program's input.

    Instead it always comes up using the laptop's microphone input as a signal source.

    Accidentally the other day, I realized that if I cranked the sound level up through the laptop's internal speaker (instead of a headphone), the internal microphone would pick it up and display it on the VA.

    This is pretty crude, but it works.

    I would like to connect the microphone input to the headphone output to do the same thing electrically. But I'm afraid of overdriving/impedance mismatching somehow letting the magic smoke out of the laptop.

    So I thought I'd ask first for advice here first.

    Also not sure if typical mic jack is stereo or mono on a modern laptop, if and when I do make up a cable.

    Thank you for your help.
     
Loading...