Pointwise asymptotics for the jumps of ergodic averages.
In this paper we prove the following results. First, we show the existence of Wiener-Wintner dynamical system with continuous singular spectrum in the orthocomplement of their respective Kronecker factors. The second result states that if , large enough, is a Wiener-Wintner function then, for all , there exists a set of full measure for which the series converges uniformly with respect to .