The Digital Model Train Part 2

50 EE March 1989 THE DIGITAL MODEL TRAIN PART 2 by T. VVigmore The second part in the series describes a locomotive decoder that is constructed in surface-mount technology. In conjunction with the associated digital control system, it enables up to 80 trains to be controlled independently. The associated control system will be described in a future article, but in the mean time the present decoder may be used with the Marklin digital system or any two-rail model track. The use of surface-mount techniques (SMT) makes it possible to construct a locomotive decoder from standard com- ponents that is compact enough for fit- ting into a locomotive. These techniques are undoubtedly new to many readers, but this article will show that there is no real mystique about them. The present decoder enables both a.c. and d.c. locomotives to be controlled in- dependently of one another. In its simplest form, it is suitable for use on tracks with a centre rail (Marklin or Trix, e.g.) or with an ove...