'Dual fuel' controller

 Having made two controllers already (first and second) I decided that I wanted a third, but with a difference. The new one is 'dual fuel' - power can come from either a wall-wart or an internally mounted 9v battery with a centre-off DPDT (double pole double throw) switch used to flick between the two.
This is what it looks like;

It's built into an 'Allstore' 0.3L box, bought from my local Rymans. 

On the left can be seen the speed controller switch, above that there's the forward/reverse DPDT switch and on the right the switch used to select either the internal 9v battery or a wall-wart. On the front there's a jack plug socket for the wall-wart.

From the rear we can see the power cable, as before I've used a Kato extension lead;

And from the underside;

The screws hold the power controller and battery box in place, and the feet were described here.

A view of the inside;

I've used a different style of power controller this time, one with a separate 'pot'. This is of course easier to mount in a box, but care needs to be taken as I'm reliably informed that the leads from board to pot are coated aluminium and a bugger to solder. I do have a spare.

Another view;

All of the wires have been left quite long to allow the lid to be lifted to one side when changing the battery. There's an LED on the board, handy as I can see if I've left it on so I don't drain the battery.

In use it works quite well, although I've only tried it on my 006 pizza so far. The idea behind it is that I can if I want set up a layout or an oval of track on a table and not have any wires trailing on the floor, which is worth considering if there's a dog in the house and I want to run trains on the coffee table. It's also been an interesting exercise in it's own right.

I think I'll call it Orac...

Paul.