wanted: device to monitor AC power via sound card

On Tue, 09 Dec 2008 10:56:07 -0400 Antonio Perez wrote: | Dumping alt.engineering.electrical I found snipped-for-privacy@ipal.net was saying: | |> I'm looking for any marketed (and UL listed, safe) product that allows |> monitoring of the AC power waveforms via a computer sound card. It would |> be good to have such a device with bandwidth up to the sound card sampling |> Nyquist frequency. It should be stable, so that once calibrated, it can |> give a reasonably accurate voltage reading for some while. But the main |> use I want this for is to monitor for waveform noise and voltage changes. |> It would be nice if it has a reasonably high dynamic range, like up to |> 600VAC/848VPP (and safe to plug into 240V). |> |> I have found a USB based device. Apparently it sends voltage levels to the |> computer, not the AC waveform. I want the waveform AND I want to do it on |> Linux, so devices like this just won't work. |> |> Anyone heard of such a thing? | | | Could this device solve it? |

I don't think so. The sound card can fulfill the role of this device. What is needed is a passive device to safely reduce the voltage from the AC supply to the level appropriate for the sound card. It needs to be safe with respect to surges and grounding.