[en] It is possible to use the Brookhaven AGS as a heavy ion machine by adding a cyclotron to the Tandem and using this combination as an injector. An intermediate step for lighter ions might consist of injecting the Tandem beam directly into the AGS. In either case it seems that quite high intensities are possible. For the past several years the Brookhaven Nuclear Physics Group has considered the possibility of adding a cyclotron to the present Tandem accelerator. As part of the proposal submitted last year to the funding agency it was shown that this Tandem cyclotron combination forms a quite suitable and realistic injector for the AGS. This paper discusses the theory and technology behind such a combination and provides the arguments by which its performance can be estimated