#Bruker epr no signal after tuning manual#

#Bruker epr no signal after tuning manual#

Manual calibration is an interactive tool to set the x-axis to the appropriate chemical with known chemical shift (e.g., a solvent).ДЄfter performing automated shimming with 'topshim'. If so, it is possible to calibrated the axis by typing 'cal', which opens a dialog box. If everything is adjusted, push: 'On' within the BSMS Control suite / Lock, and it should lock. It may be convenient to adjust the stepsize. When you adjust the values within the BSMS Control Suite, please make sure that the cursor does not leave that window.

If the lock signal is not symmetrical: BSMS Control Suite/Lock -> Select: Phase -> Adjust phase. (Optional: Power, but be careful because of power saturation effects) If the lock signal is too big or small: BSMS Control Suite/Lock -> Select: Lock gain -> Adjust gain. If the lock signal shows no signal, or is not centered: BSMS Control Suite/Lock -> Select: Field -> Adjust Field Probably you have observed this kind of image many times for many successfully locked samples. The goalВ of locking is to have a lock signal displayed that is symmetrical and centered, not too small or too big, with significant ringing. If it locks, fine, if it doesn't, please continue with manual locking. Please go to the LOCK tab.Д¬lick on 'Auto LOCK' and wait for about 1 minute. Make sure that you have the BSMS Control window open. Do you have enough liquid, did you really add deuterated solvent, and is the sample placed within the gauge correctly, did you read an appropriate shim file with 'rsh'?

Make sure that you followed the 'NMR-basic-operation' procedure, in particular, make sure that you followed the procedure about sample preparation.

If the sample does not lock, please do the following:

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