Analysis of JHMBC using Sparky
From NMR Wiki
Open the spectrum
Assign HMBC peaks and label them using these Sparky commands
Read splittings in F1 dimension for the peaks (dublets) of interest. Divide splitting in Hertz by the scaling factor that was used to set up your experiment.
Sparky itself is not very good at displaying spectral axes in Hertz - so you might have to determine splittings in ppm then recompute them in Hertz units.
This deficiency may be overcome by writing a special plugin script in Python programming language.