  We perform experiments and phase model simulations with a ring network of
oscillatory electrochemical reactions to explore the effect of random
connections and non-isochronocity of the interactions on the pattern formation.
A few additional links facilitate the emergence of the fully synchronized
state. With larger non-isochronicity, complex rotating waves or persistent
irregular phase dynamics can derail the convergence to global synchronization.
The observed long transients of irregular phase dynamics exemplify the
possibility of a sudden onset of hyper synchronous behavior without any
external stimulus or network reorganization.
