NMR Facility Maintenance

Weekly Maintenance Tasks

1. Tune and Match the probe
2. Measure the lock value (Z0), lock power, lock gain, lock phase for CDCl3 standard
3. Optimize the shims; measure resolution at 50%, 0.55%, 0.11% of line height with sample spinning and non-spinning; measure spinning sidebands; save the optimized shims and replace the old "stdshim" file (accessible from 'GetShim' button) with this new shim file.
4. Measure the 90 degree pulse length for each default direct-observe nucleus; edit standard parameters to use this 90 degree PW.
5. Measure the 90 degree pulse length for the 1H decoupler ("pp" pulse length); edit standard parameters to use this 90 degree PW.
6. Purge water from VT unit (turn off VT unit, disconnect from probe, let stand for about 1 hour, reconnect and turn on VT unit).
7. Fill magnet with liquid nitrogen
8. Check level of liquid helium; compare rate of helium boil-off with previous rates.
9. Check workstation disk capacity; archive data if disk > 90% full
10. Check that printers and accessible from spectrometer and that printers are functional.

Bimonthly Maintenance Tasks

1. Calibrate the 1H decoupler for heteronculear decoupling; adjust the 13C standard parameters for optimized 1H decoupling.
2. Check pulse amplitude stability
3. Check pulse phase stability
4. Check pulse incrementation linearity
5. Check dynamic range of receiver
6. calibrate PFG recovery profile
7. Measure signal/noise for each nucleus
8. Measure pulse length homogeneity
9. Measure quadrature images
10. Check the air cushions on the anti-vibration legs
11. Fill the magnet with liquid helium.
12. Calibrate the low temperature range: Compare the temperature listed on the VT unit with the temperature measured with the methanol sample at 20C, -10C, and -40C
13. Calibrate the high-temperature range: Compare the temperature listed on the VT unit with the temperature measured with the ethylene glycol sample at 20C, 50C, and 80C

Special Maintenance Tasks

1. Set-up of the I500 for Dr. Martin Stone