ni signal express labview

[Hani_NL]

Dear there

am trying to use the NI labview signal express to loge data from my Tektronix TDS 2022B oscilloscope using the limited edition of the NI labview signal express Tektronix edtion.2.5 . I have an infrared channel that react quite sensitive on human bodies who walk cross the line of sight between the receiver and the sender,when I measure the output of the receiver directly on the oscilloscope react my circuit pretty fast and sensitive to any changes due to human body effect walking through the channel path.

I want to use the labview signal express to log the data (output of the receiver) over a period of time,But what happened after I download it the software, the connection between the oscilloscope and the PC using USB slot got a huge delay,in my point of view.

the signal that I got on my screen or on the view data is too slow according to the normal situation on the oscilloscope(without using the software)

therefore  the software become no fast enough to follow the cut off situations if a couple of people moved into the channel or one person walks pretty fast back and forth.recording data in this case has no meaning cause the logged data has an error by fast movements scenario.

I didn't have this situation when my receiver is connected only to the oscilloscope,it means my cirrus is quite sensitive enough but is the software that I can't deal with.

Does any one have any idea what am doing wrong,I know it is the right software and the program recognized my oscilloscope ?

and by the way is there any other way to loge data from a simple hardware ?

 I just need to record data over a period of time to analyze the cut off situations caused by human body passing by.

thank u very much for reading my question.

Message Edited by Hani_NL on 11-13-2008 06:16 PM

[Burban]

Hani_NL,

I am assuming that the connection between your PC and your Oscilloscope is USB 2.0. The reason why you are now seeing a downgrade in the refresh rate of your screen on your Tektronix scope is due to the processing power now having to be split by the instrument to communicate with the PC that is running Signal Express Tektronix Edition 2.5 and that of its video output. The scope cannot handle both tasks simutaneously.

Although the displays on your Oscope and the PC with Signal Express Tektronix Edition 2.5 might be showing a slower refresh rate, the data is still being taken and recorded at your desired rate. One option you can look into, is the possibility of a faster PC to run Signal Express on, as this has proven useful to some users in the past who were on older PC's.  You could also try sampling at a slower rate.

Regards,

[felixk]

G'day,

Was wondering how you sample at a slower rate?

Thanks

Paul

[felixk]

G'day,

Was wondering how you sample at the slower rate?  It says in the step options that you can not change the min sample rate from 2500.

Thanks

Paul