Ok, I am confused, why would a power supply kill a loco motor, unless it was giving out a voltage higher than that required by the motor. Half wave rectification, just means that the whole signal is not being used, and generally the motor should filter it, so it should be a lower voltage, unless I am missing something. In electronic power supplies, we use full wave rectification as you don't need such a large smoothing capacitor. From my experience of model railways, other than the advent of better motors and DCC, the basic electrical stuff from the major suppliers doesn't seem to have moved on a lot. Peco still sell a slider switch that fits under a point motor, that puts extra load on the motor, and when they do redesign it to a supposedly better one, it is too large and falls apart if you look at it. The joke of it is, the basic Peco point motor is brilliant, it is simple when fitted under the point, and because it is direct, works well, the thing that they got wrong, is not selling a piece of card to fit below the point so you don't see the gap or better making an adapter where the motor fits below the point, which the point fits on top of. There miniture microswitches on EBay that are much better and more reliable. The biggest issue with old controllers seems to be their overload protection, if the tracks short out, there is no visible indication. At least with the ready old Hornby ones a button used to pop out. I would imagime the cost of a large transformer is the reason they are not made any more.
