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Z31980_00_03
Installation
use the field value to shift the proton resonance line to that value on the 1H frequency
scale. A rough value for the field shift is 20ppm/1000 field units. It depends a bit on the
actual shim board but can be a good starting point for all Fourier systems.
There is no need to be exact at this point. A spectrum like this is close enough. Using the
resulting field value, the Fourier must be able to lock the field in the automatic mode.
6.10 Converting the Parameter Set to the actual BF1
Since the shimming process may have an effect on the B0 field, it may be necessary to
redefine BF1 after Shimming and Lock have been optimized. The ideal BF1 is close to
300.18 when the Lock Field DAC is close to 2000 (±500).
When you are satisfied that you have a good BF1 and the LOCK DAC is near its center,
repeat "CF and expinstall" with the new BF1.
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