  The algorithms for position reconstruction in silicon micro-strip detectors
are studied, and the signals of a minimum ionizing particle are simulated. The
center-of-gravity distributions of the data events allow the fine tuning of the
signal forms and of the strip response functions. In the sensors with floating
strips the response function turns out to roughly approximate the response of a
triangular function for the size of the signal involved. The simulations are
extended to non orthogonal incidence. In these directions, and in general for
all the asymmetric signal distributions, the standard application of the $\eta$
algorithm introduces a systematic error. A signal reconstruction theorem gives
the way to implement the corrections of this error.
