Efficient Sound Card Based Experimention At Different Levels Of Natural   Science Education
  Sound cards, which count as standard equipment in today's computers, can be turned into measurement tools, making experimentation very efficient and cheap. The chief difficulties to overcome are the lack of proper hardware interfacing and processing software. Sound-card experimentation becomes really viable only if we demonstrate how to connect different sensors to the sound card and provide suitable open-source software to support the experiments. In our talk, we shall present a few applications of sound cards in measurements: photogates, stopwatches and an example of temperature measurement and registration. We also provide the software for these applications. 
Zoltan Gingl, Robert Mingesz, Janos Mellar, Balazs Lupsic and Katalin   Kopasz
physics.ed-ph physics.ins-det physics.pop-ph