Virtual Instrument technology which is powerful, flexible and convenient is the developing trend of measurement technology. Compared the sound card with the DAQ( data acquisition), it is found that a real-time and high SNR( signal noise ratio) sound signal acquisition system can be designed using the sound card in computer.
The Virtual Instrument based on PC sound card has the virtues of low cost and powerful generality,and the sound card can take the place of the plug-in data-acquisition board on low-frequency condition . In this article, the virtual double-traced storage oscilloscope based on sound card, whose function and interface were designed according to the actual oscilloscope, was developed using Virtual Instrument soft are LabVIEW and its digital sound record nodes.
This article designs a kind of simple double channel oscilloscope with the ordinary 16 sound card. It can gather the signal. Transfer through LabVIEW sound function that oneself offer sonic card can show the wave form of the input signal. Utilizing left and right sides pairs of sound channel of sound card to dispose many pieces of sonic card walk abreast job can gather a lot of multi-channel signal. Therefore the data acquisition system structuring the low cost with the sonic card is really feasible.
Keywords: virtual instrument; sound card; oscilloscope; acquisition system