It’s a tricky one isn’t it? I don’t know if they ever really took off, but you’d imagine that a complete original set like this could become a bit of a collectors item in a few years time?
I wonder if anyone on the forum has ever used one (or even seen one in action)?
Yes, I have 'Mallard' (complete set), 'Flying Scotsman' (bought new) and 'Dwight D Eisenhower' (bought second-hand at the last Chiltern Model Railway show that took place at the St. Albans Arena). I built a small layout on which I could run both ordinary 00 locos and the steam locos, using a form of cab control but with relays under the baseboard to switch the high-current power for the steam locos. The layout is currently out of use as I made the mistake of using the soft Sundeala(?) for the top surface and it really needs a complete rebuild. So every now and then I give them a run on my rolling road, usually as something to do around Christmas/New Year!
The control system is unique. The power to the boiler is varied by using pulse-width modulation and when the throttle lever is moved, the voltage is altered by a set amount depending on the direction the throttle is moved. This is detected by a chip on the loco which activates a servo on the loco which controls a steam flow and direction valve. Thus speed and direction are controllable.
Had they actually made the control system DCC compatible, I think they would have sold many more than they did.