  The 3 MV Tandem Pelletron accelerator at the Spanish Accelerator Laboratory
(CNA) has been recently upgraded to produce pulsed ion beams for neutron
Time-Of-Flight (TOF) measurements. The upgrade has consisted of two actions: a
pulsing system installed at the low energy part of the Tandem accelerator and a
new line fully equipped. The pulsing system provides approximately one
nanosecond pulse width of protons with variable repetition rates from kHz down
to MHz. The new line is equipped with conventional devices and a pick-up for
timing measurements with high resolution. The properties of the whole system
have been tested under various working conditions and they are described in
some detail.
