Agilent Technologies VARIAN Dual, Manual, Page: 17 / 30

Dual and Dual Broadband NMR Probes
16
Dual and Dual Broadband NMR Probes Installation 01-999124-00 J 0606
2. Plot the spectrum again using a large enough value of
wp
to show all the spinning
sidebands, including fourth order.
3. Measure spinning sideband amplitudes as a percentage of the peak.
Spinning sidebands occur at frequency intervals on either side of the central peak
equal to the spinning rate.
The standard test requires
nt=1
or
nt=4
. Do not repeat the test at
nt=16
if the
sideband specification is met at
nt=4
.
4. Write the results for each probe in the forms provided in Test Results, page 27 .
13
C Sensitivity
The specification for the
13
C spinning resolution and lineshape test must be met before
performing this test.
1. Enter
rtp('/vnmr/tests/C13sn') su
.
2. Tune the probe.
3. Set the
13
C 90
°
pulse width to the value determined in
13
C Observe 90° Pulse
Width, page 14 .
4. Enter
ga
.
Wait at least 8 minutes between acquisitions to ensure that the C
6
D
6
lines are fully
relaxed.
5. The signal of interest is the highest line of
the C
6
D
6
triplet (see Figure 6 ).
Use the cursors to select the best 1400 Hz
noise region between the dioxane and
benzene peaks.
6. Enter
dsnmax(1400)
.
The computer calculates the S/N ratio.
7. Answer
'y'
to plot the results.
8. Write the results for each probe in the forms
provided in
Test Results, page 27 .
15
N Observe 90° Pulse Width
Use this procedure to determine the
15
N PW90 value to be used in the
15
N sensitivity test.
1. Enter
rtp('/vnmr/tests/N15sn') su
.
2. Tune the probe observe channel without using the filter.
3. Change
dpwr
to the
1
H
γ
H
2
value used in the procedure WALTZ
1
H Decoupling
Using High-Performance RF Waveform Generator. If a High-Performance RF
Waveform Generator is not present, use the procedure for WALTS
1
H Decoupling
Using Pre-programmed Pulse Modulation.
4. Change
dmf
to 4*
γ
H
2
.
5. Enter
ga
.
6. Enter
dm='yyy' d1=45 su
.
7. Determine the correct
tpwr
as follows:
a. Enter
tpwr=50 pw=7 ga
.
Figure 6.
13
C Sensitivity
Hz 7000 8000 9000 10000 11000 12000 13000 14000
p-Dioxane Benzene-d
6