  Experimental projects using spherical antennas to detect gravitational waves
are nowdays a concrete reality. The main purpose of this paper is to give a
possible way of interpreting output data from such a system. Responses of the
five fundamental quadrupole modes and of the six resonators in TIGA
collocations are shown as a function of the incoming direction of the incident
wave. Then, for a source lying in the galactic plane, sidereal time and
galactic longitude dependence is given. Thus, once a candidate source of
gravitational waves is considered, we can exactly predict the resonators'
response as a function of time.
