Bench test factory Mopar tachometer

I was thinking about the sound out of a phone/laptop myself. I have a waveform generator I could rig up. I believe its a 5V output.
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Heck, even my uber cheap component tester has a frequency/PWM generator/counter.....you could probe your tach input with this and measure the frequency by dividing by 8 and comparing what your tach says.
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