S.B. Karavashkin and O.N. Karavashkina, Special Laboratory for Fundamental Elaboration SELF; e-mail: selflab@go.com , selflab@mail.ru ; http://angelfire.lycos.com/la3/SELFlab ; http://angelfire.lycos.com/la3/selftrans Some features of the forced vibrations modelling for 1d homogeneous elastic lumped lines (237K, Postscript) ABSTRACT. In this paper we survey the conventional methods to calculate the systems modelling vibrant 1D elastic lumped lines, in comparison with the new non-matrix method to obtain the exact analytical solutions for such systems. We consider the features arising when an external force acts on an interior element of such system. We analyse the conditions of the limiting process to the distributed lines and derive the conditions, when a lumped line can be modelled by the methods conventional for distributed lines.