This paper presents the implementation and evaluation of a block cryptosystem based in chaotic maps. The noise function used in this cryptosystem is an approximation to the chaotic tent map, and for this reason, it is named pseudo chaotic tent map (PCT map). PCT map has been analyzed and evaluated using the statistical mechanic tools such as: bifurcation diagram, Lyapunov exponent and invariant distribution. In order to determine the influence of PCT map in the syntactic, semantic and statistic of a message, this map has been used on the non-balanced and dynamic network proposed by Kocarev. Cryptosystem has been evaluated using concepts of the information theory, such as: entropy and mutual information. The randomness of the produced cryptograms has been evaluated using the statistical tests suite of NIST.