VNMR TRICKS - ADDING SCANS ONCE THE ACQUISITION HAS FINISHED
There is a workaround that still allows you to add scans to a
completed experiment. Let's assume you have the acquired data in exp1; to
add extra scans you can now use
mp(2) jexp2 nt=extra_nt go
Once that experiment is complete, or when you have accumulated enough extra
signal, you can use
clradd jexp1 add jexp2 add
jexp5
setvalue('nt',<nt + extra_nt>,'processed')
setvalue('ct',<ct + extra_ct>,'processed')
wft
This does not work for arrayed or multidimensional datasets.
A Historical Note
On a GEMINI, XL, or VXR, (older spectrometers that are not avaialble at IUNMR)
it was possible to increase NT and resume
the acquisition using RA, even after the completion of an experiment. It was
even possible to retrieve a dataset that was saved using SVF, increase NT and
still type RA, long after an the original dataset was acquired. This was possible
because our PASCAL (P-Code) based software stored the acquisition
instructions (Acodes) together with every FID trace, in the data block header. Only when
a dataset was saved using SVCF ("compressed" mode), the acquisition
instructions were lost (SVCF reduces the block headers to one sector), and RA was no
longer possible. VNMR (software used on all IUNMR Varian spectrometers)
never had this feature, as it stores the Acodes in a separate file in
/vnmr/acqqueue, and this file is deleted once the experiment is complete. In
VNMR, "sa nt=<nt+extra_nt> ra" is only possible DURING an ongoing
experiment.
P>
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Last updated: June 9, 1999
URL: http://nmr.chem.indiana.edu/NMRguide/1dexpt/add_scans.html
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