How far can a soundcard based test & measurement system - RF Cafe Forums

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TestGuru
 Post subject: How far can a soundcard based test & measurement system
Posted: Tue Nov 21, 2006 3:33 am 
 
Lieutenant

Joined: Fri Nov 17, 2006 6:10 am

Posts: 1

Almost every PC or Pocket PC have a built-in sound card. Sound cards

are usually treated as an audio input and output devices for recording,

synthesizing, and replaying speech, music and songs. However, sound

cards can do more than that.

From instrumentation and control point of view, a sound Card is a dual

-channel A/D and dual-channel D/A device, which has a flat frequency

response in audio frequency range and have a sampling rate of up to

192kHz, sampling depth of up to 24 bits. Even without any external

attenuation circuit, it is able to measure a signal from down to 1 uV

to 1V, thanks to its built-in gain control (like Mic Boost, Mic Volume

and Line Volume).

Measurement accuracy depends on its hardware quality. Normally, an

internal standalone sound card is better than an on-board sound card (

chip), and an external sound card is the best. Professional grade sound

card is better than consumer grade sound card. In terms of price, even

the professional grade sound card is much cheaper (a few times

normally) than its peers in A/D and D/A cards.

The accuracy of the clock reference is 0.00x% typically for an ordinary

sound card. For example, a 0.003%'s inaccuracy in a sampling rate of

44100 Hz means an error of only 1.3Hz. The noise level of a good sound

card can be below -100dB, THD below 0.0029%.

So, what can be measured by a sound card. Well, it can measure any

signal perfectly within audio frequency range, like vibration signal,

rotational speed, heat and Lung sound, ECG....., depending on the

sensor used, and of course, depending on the software used. A good one

can be found at: https://www.virtins.com. It is FREE to download and

try.

website: https://www.virtins.com

PC version: https://www.virtins.com/SCMISetup.exe

Pocket PC version: https://www.virtins.com/PocketINSSetup.exe

Virtins Sound Card MultiInstrument consists of a sound card dual trace

oscilloscope, a real time spectrum analyzer, and a signal generator and

can run them concurrently. It features a specially designed data

acquisition approach, which is able to monitor the input signal

continuously without missing any trigger event before a frame of data

is collected. It has a very fast screen refresh rate. It supports

sophisticated triggering method including pre-trigger and post-trigger.

A comprehensive range of functions are provided, including waveform

addition and subtraction, Lissajous Pattern, transient signal

recording, voltmeter, RMS amplitude spectrum, relative amplitude

spectrum, octave analysis(1/1,1/3,1/6,1/12,1/24),THD, THD+N, SNR,

SINAD, peak hold, phase spectrum, auto correlation, cross correlation,

function generation, multitone generation, arbitrary waveform

generation, white noise and pink noise generation and sweep signal

generation. It Supports 8, 16, 24 bits and multilingual user interface,

including English, French, German, Italian, Spanish, Portuguess,

Simplified Chinese, Traditional Chinese, Japanese, and Korean

Image

Image


 
   
 
Mr.Whatever
 Post subject:
Posted: Sun Nov 26, 2006 1:08 pm 
 
Captain
User avatar

Joined: Fri Apr 07, 2006 6:10 pm

Posts: 20

Interesting. Thanks! I've been looking for something like this.

Posted  11/12/2012