> I've found that converting digitally oversampled Avance data to the analogue
> form using "convdta" leads to an incorrectly calculated TD in acqus - 122
> points (the magic number for oversampled data) less than it should be.
> Although slices in F2 appear fine in 2D experiments, it wreaks havoc when the
> F1 transform is applied. Setting TD to the correct value overcomes this
> problem.
It is not true that datasets generated by convdta have wrong TD values;
TD is actually decreased and the correct value documented in acqus.
Note however, that all fids in a ser file start at 1K byte aligned
addresses; so despite decreased TD in acquisition dimension convdta may
not reduce the size of the new generated ser file.
For 3rd party software, which is unable to handle this 1K byte alignment,
it may be a workaround to fake acquisition dimension TD to the next
multiple of 256. This should never be done inside XWIN-NMR, as baseline
correction, window multiplication and linear prediction (all working on
TD data points) give incorrect results.
-- Werner Mausshardt E-mail: wem@bruker.de Software Department Tel: +49 721 5161 448 Bruker Analytische Messtechnik GmbH Fax: +49 721 5161 437