Standard ¹⁹F sensitivity test sample: 0.05% Trifluorotoluene in chloroform-d.

Record a ¹H-coupled ¹⁹F spectrum.

The calibration of the ¹⁹F sensitivity test is performed using the standard ¹H-coupled ¹⁹F parameter set (the pulse program is set to pulprog zg).  

It is very important to use a long recycle delay, usually d1=5*T1(¹⁹F) (for instance d1=20 s). Use a single scan (ns=1).

Set p1 to the 90º ¹⁹F observe pulse at high power level pl1. This pulse is calibrated reaching the maximum signal for 90º and null point in 180º.

. Reference the line to -63 ppm (CFCl₃ = 0 ppm) and plot the full spectrum.

  Plot the noise with a minimum amplitude of 1.5 cm over a minimum of 500 Hz.

 Good signal to noise can be obtained with good resolution and lineshape only. To check the resolution use no linebroadening before transformation and measure the splitting in the center of the multiplet. The splitting should be deeper than 60%. If this condition is fulfilled use a line broadening factor of 2 Hz for transformation.