2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/27616Jacobian elliptic travelling wave solutions for a new Hamiltonian amplitude equation determining some instabilities of modulated wave train are obtained. By mere variation of the Jacobian elliptic parameter $k^2$ from zero to one, these solutions are transformed from a trivial one to the known solitary solutions.6 pages, no figure, latexCondensed Mattertext