Varian UNITY INOVA NMR, Hardware Installation, Page: 20 / 65

2.3 Pulse Sequences Proton Multipulse NMR
01-999044-00 C0501 UNITY INOVA Solids Hardware Installation
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Operation with a shorter
d1
may cause an error (fifo underflow) and halt the acquisition. If
an underflow error occurs, decrease
np
or increase
d1
. Run with
bs='n'
if possible. Once
a fifo underflow error has been generated it is sometimes necessary to run one scan
successfully with a small number of points (say 2k) before continuing.
2.3 Pulse Sequences Proton Multipulse NMR
The pulse sequence source files
flipflop.c
,
br24.c
,
cylbr24.c
,
mrev8.
c, and
cylmrev8.c
must be modified to function with UNITY INOVA and VNMR 5.2F.
For
UNITY
INOVA, the receiver is off by default (it is on for UNITYplus). When using explicit
acquisition, the receiver is turned on with the beginning of the
'acquire'
statement. For
CRAMPS, this is too late—the receiver must be turned on at the beginning of the delay
'dtau'
.
Place
rcvron()
before the
delay(dtau)
or
delay(dtau + tau)
and before
rcvroff()
after the acquire statement in each sequence.
16k >0, acqi, 2D, or array 0.1
8k >0, acqi, 2D, or array 0.05
np bs d1(s)