model railway monitor panel

gotamilir Many railway modellers would love to have a track monitor panel, but, unfortunately, the few commercially available types do not justify their cost. It is, however, not too difficult to make one yourself. The reproducing of the track diagram and the mounting of the monitor lights on the panel can be ac- complished without too much trouble. There is a problem, however, in indicating the position of turnouts and colour-light signals, because these elements are normally operated by spring-loaded switches to prevent the burning out of the solenoids. After the push-button on the control panel has been released, the supply line is no longer live and can, therefore, not be used for lighting an indicator. This problem can, fortunately, be solved by a couple of R-S bistables (NOR gate latches). The push-button switches and solenoid coils shown in figure 1 are those already contained in the railway set-up. Note that the system is as- sumed to operate from a 9 . . .15 V AC supply. ...