If you don't know what JMRI and WiThrottle are, read on.

I recently bought a USB interface board for my NCE DCC system. I got this from my friend Kevin Dickerson at  Coastal DCC who, fortunately, lives just round the corner from me in Ipswich.

The USB card connected my iMac to the NCE system. I had to install a new driver but I got that from the  NCE USB web page. I already had  JMRI (Java Model Railroad Interface) installed so, once I had created a new profile and connected that to my NCE, I was able to control my trains from the iMac screen. It gets better though.

JMRI provides a wireless connection for external throttles to drive trains through the USB link. I downloaded WiThrottle from the App Store and installed it on my iPad and iPhone. This quickly connected to JMRI and I was running my trains (and controlling all the sound effects) from my iPhone.

It gets even better! The following took a bit of time to work out but this is what I did.
 

1. I created a control panel using PanelPro. Initially, I drew a schematic of the whole railroad. When doing this, you create a list of existing turnouts and connect one at a time to the turnouts on the schematic. None of my turnouts are powered so I used internal definitions. I included the turntable but I was at a loss what to do next. After a lot of fiddling around - the documentation is lousy - I got there. There is no beginners guide at all so it is a case of try and try again.
2. I worked out that I could add a turntable to the schematic. I then defined 5 more turnouts using NCE definitions, numbering them 1 - 5 (as I have 5 roads on my turntable).
3. I purchased the full version of WiThrottle for the princely sum of £6.99 but could see no way to control anything! I e-mailed the WiThrottle people but they had obviously not come across a turntable before so weren't much initial help.
4. I sat down this morning with a clear head and decided that I could get this. Firstly, I realised that I needed to put the actual accessory code for each turnout - instead of 1 I needed to put 255, for instance. 255 is the accessory that is defined for the home road on the turntable. I deleted the existing definitions and replaced them with the correct ones. Then I applied these to the schematic. I clicked on one road and found that the turntable was turning correctly!
5. All that was left was to find out how to operate this from the iPhone. Next to the throttle on the screen is a number pad for the various functions. I had been swiping left to change the pages to see the higher functions. Suddenly, for no apparent reason, I swiped right and found a list of turnouts. There, amongst the long list, were the 5 turntable turnouts. Done!
6. The only thing left to do was to go back to the schematic and delete all of the layout except for the turntable. I then deleted all of the internal turnout definitions. On going back to the iPhone, I found that the turnout list now only comprised of the 5 for the turntable. Job done!