In six years of operation (1996-2002) the PDS instrument on board the BeppoSAX 
satellite provided a large amount of data on a good fraction of the hard X-ray 
(15-200 keV) sky with unprecedented sensitivity, due to its good performances 
in terms of stability, background level and calibration. 
In order to build a PDS data archive we performed a detailed study of possible 
systematic effects that can affect the PDS background and found that nor the 
ones of instrumental origin nor the ones due to background fluctuations are 
significant. This result was used to confirm the presence, in the Coma Cluster,
of a non-thermal hard X-ray component in excess of the thermal emission at 
~4.8 sigma confidence level. Then we focused on the determination of the 
cosmic diffuse X-ray background (CXB) spectrum. Because the measurement of the 
unresolved CXB requires the knowledge of the intrinsic instrumental background 
level, for this purpose we used the spectra obtained when the PDS was observing
the Earth (as a by-product we measured the 15-50 keV Earth albedo spectrum, 
too). We find that our 15-50 keV CXB spectrum is in agreement with that 
measured by HEAO-1 more than 25 years ago, and therefore the disagreement by a 
factor up to 1.5 with respect to low (<10 keV) energy measurements is confirmed.