Spin Echo Spectrum
==================

The following example shows how to acquire an NMR spectrum with a spin-echo based spectrum sequence written in pypulseq.
The example can essentially be broken down as follows:

#. Create an ``AcquisitionControl`` using the default device configuration from the repository. 
   Here we can also set the log level for the log-file and the console log-output.
#. Construct the spin echo based spectrum sequence. 
   Here we use 20 ms echo time and 200 us RF block pulse duration.
#. Define the most basic ``AcquisitionParameter``, namely the Larmor frequency :math:`f_0` and the decimation factor for DDC. 
   Note that acquisition parameters are defined globally. 
   They are saved on mutation and the latest state is loaded at ``AcquisitionControl`` instantiation using the provided path or the default.
#. Execute the experiment.
#. Extract the down-sampled raw data.
#. Apply FFT to obtain the spectrum and calculate the associated frequency axis.
#. Plot the magnitude spectrum.
#. Add some note to the meta data of the ``AcquisitionData`` and save the results using the ``write`` method.
#. Delete the acquisition control. This is an important step, as the destructor ``__del__`` of the ``AcquisitionControl`` class disconnects from the measurement cards.


.. literalinclude:: ../../../examples/spinecho_1d.py