synchronize signals

[jool]

Hello,

i am new to DIAdem and labVIEW. i have acquire signals with labVIEW with two different DAQmx steps with different frequencies.

When i plot them in DIAdem they are slightly out of sync. the first DAQmx sampled in 50 Khz is about 0.03 s ahead of the second DAQmx sampled in 80 KHz.

my question is how can i shift the time for one of signals so when I plot them they will be synchronized. is there an easy way to do it in DIAdem (2010)

Thanks

Gal

[Kyle_M]

Gal,

TO make sure I understand the issue, we just want to offset the start time of a channel by .03s to sync two channels on a graph, correct? If so, you can simply convert them to waveform channels in the analysis tab, then change the "waveform x-offset" to the appropriate value for them to be sync'd. This is usually the simplest method to adjust the timing. 

Regards,

Kyle Mozdzyn

Applications Engineering

National Instruments

[jool]

Hi Kyle,

Yes you uderstood me correctly.in the attachments you can see ihave two groups of signals. i want to sync them.  one small doubt....in the meta file i have found the exact time of the log start. i took the differrence betweenthe two groups calcualted as (log start 1 group) minus (log start 2 group) of 0.031 s and put it as my offset. i still have a slight offset remain between them. when i put a value of 0.034 the signals look in perfect sync. is it possible? or that my signals are suppose to be slightly in offset

thanks

Gal

[Kyle_M]

Jool,

The meta may have the files created at the same time, but that is only accurate to the second, so any sub-second offsets, like the ~.03 seconds youre seeing could easily be present. 

That said, do realize that the data was taken when your non-offset times say they were, so if youre comparing the two files, they were technically showing the correct real-world times already. Its hard to say whether you should offset them without knowing what they represent or whart the data is used for. I just want to make this known so you can correctly interpret the data and not offset them just so their start points are the same, but instead so the data represents their actual time difference in the real world. 

Regards,

Kyle Mozdzyn

Applications Engineering

National Instruments