  We present the results of BeppoSAX AO1 Core Program observations of 3C~273
performed in Jan. 1997 and compare them in detail with data obtained during the
satellite Science Verification Phase (SVP), in Jul. 1996. Though a power law is
an acceptable representation of the data in the whole 0.1-200 keV range, there
is indication of a steepening of the spectrum as the energy increases. Our data
mark a difference with respect to the SVP data, where a steeper power law below
0.5 keV, an absorption feature at 0.6 keV, and a more prominent fluorescence
iron line have been found. The weakening of cold/warm matter signatures in our
data with respect to the SVP ones may indicate that, at higher luminosities,
the featureless continuum produced in a relativistic jet overwhelms any thermal
and/or reprocessed radiation, while the two components were almost comparable
during the lower state of Jul. 1996. We conclude that this radio--loud source
shows evidence not only for thermal disk--like emission, but also substantial
reprocessing of X-rays onto cold matter.
