Re: No phase cycle in 2.5

Andrew Gibbs (andrew.gibbs@bruker.co.uk)
Fri, 18 Jun 1999 10:14:23 +0100

> We have a problem on a new DBX system. Xwinnmr 2.5 will not phase cycle
> correctly. If we run the zg sequence with ns=8 the fids will cancel out
> after the 8 scans. We believe that the transmitter is phase cycling
> correctly and that the problem is due to the receiver not phase cycling at
> all. If we set all phases to zero then the FIDs will add up correctly.
>
> This system is also running xwinnmr1.0 to use with Paravision, and the
> problem does not occur in xwinnmr1.0. Hence it does not seem to originate
> in harware but in some problem with xwinnmr2.5. The problem has been with
> us since we first startted using the system 3 months ago.

One thing trivial thing to check is the phase preset times in the
spectrometer constants table (edscon -> PHASPR) - if someone has
mistakenly changed these values to zero then you will see this effect,
especially if your pulse lengths are short.

Andrew

-- 
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