Using the ESU Mobile Control II with the ProMiniAir Transmitter for Dead Rail

The ESU (the LokSound decoder manufacturer) Mobile Control II (shortened here to “ESU MC II” or “MC II”) is an Android device that is specialized for throttle control of model railroads. ESU designed the MC II as an “open” platform for developers to adapt their throttle apps to the throttle-specific features of the MC II. ESU provides an excellent summary of the device here, which is excerpted here:

Since smart phones with touch screens have almost completely replaced the conventional mobile phone, model train enthusiasts and manufacturers face the question how to employ more powerful devices for controlling model trains. As a result of this, many apps have been developed lately, which can be uploaded onto your mobile phone and used for running your trains.

This concept, however, has one disadvantage, namely that smart phones have not been primarily designed for running model trains. Due to the lack of suitable input elements the operator is forced to spend most of the time looking at the display. The limits become quickly obvious, once the battery of the phone has been discharged and nobody can reach you by phone anymore.

We at ESU had a look at the question on how to utilize the advantages of the smart phone technology and combine it with the needs of model train enthusiasts.

It is with great joy that we now present the results of our considerations. With the new Mobile Control II you have wireless control of your locomotives, accessories and routes simply by radio control!


In this post, I’ll show you how to use the ESU MC II with the ProMiniAir Transmitter integrated with a WiFi-equipped EX-CommandStation (PMA Tx/WCS for short), which can be found on eBay here.

The components and their connections are shown below.

The connections between the ESU MC II, the WiFi-equipped EX-CommandStation, the ProMiniAir Transmitter, the onboard ProMiniAir Receiver, and the onboard DCC Decoder.

I thank one of my customers, Jeffrey Fonda, for the idea of this post.

How to Set up and Use the ESU MC II with the ProMiniAir Transmitter/WiFi-Equipped EX-CommandStation

Before getting started, it’s useful to know the MC II is essentially a small Android tablet with specialized “haptic” inputs designed to control model railroads. This knowledge will help you navigate the MC II if you are familiar with Android devices.

The ESU MC II I received already had the well-known “Engine Driver” Android throttle app installed (see here for the Engine Driver homepage). If it’s not installed on your MC II, it’s easy to download the Engine Driver app from the Google Play Store.

Note: in some photos below, you might notice the wiring at the bottom of the MC II is NOT a USB connection. I inadvertently broke loose the internal USB socket, and I repaired it.

The sequence of photos below shows you how to connect the MC II to the PMA Tx/WCS’s WiFi network, start up the Engine Driver app, set its defaults and options, and finally use it as a throttle to control Dead Rail locomotives.

The ProMiniAir Transmitter is integrated with a WiFi-equipped EX-CommandStation. The EX-CommandStation receives WiFi commands from the Engine Driver app running on the ESU MC II and outputs DCC to the ProMiniAir Transmitter for transmission to compatible onboard Dead Rail receivers such as the ProMiniAir Rx, Airwire CONVRTR, Tam Valley Depot DRS-1, Stanton Cab, and Gwire. The PMA Tx/WCS+CNV is available on eBay using the “ProMiniAir” search string.
The opening screen on the ESU Mobile Control II. To get started, you find the EX-Command Station’s WiFi.
Now select Wi-Fi…
Now select the DCCEX WiFi.
The first time, enter the obvious password.
You are now good to go with the WiFi, and now exit back to the “home page.”
Now select the Engine Driver app.
Once Engine Driver is selected, now select the appropriate DCCEX WiFi.
You are now ready to select your locomotive. The DCC will be sent from the EX-CommandStaion to the ProMiniAir Transmitter and then out the onboard Dead Rail Receivers.
Enter the DCC address and select “Acquire” to initiate the DCC commands to the selected locomotive.
You now control the locomotive as you normally do with the Engine Driver app.

Changing Configuration Variables (CVs) with Engine Driver on the ESU MC II

On another webpage, I provided some “workaround” solutions for changing the Configuration Variables (CV) of a DC decoder onboard a Dead Rail locomotive using the PMA Tx/WCS. The specialized solutions arose because DCC-EX commands provide this capability, but most throttle apps still need to. Fortunately, the Engine Driver app has this capability but requires activation of DCC-EX features, as shown below.

First, start the Engine Driver app as shown below.

I recommend selecting and enabling the DCC-EX options, allowing you to change the Decoder Configuration variables (CV) easily.
Select to get started with DCC-EX options.
You select this option to turn on various DCC-EX options.
I enable both of these options to take full advantage of the EX-CommandStation.
After exiting from setting the DCC-EX options, you can select DCC-EX to change decoder CVs.
Now select Program on Main from the pulldown to send change of CV value commands ONLY to the locomotive address specified.
You select the DCC address, the CV number, and the CV value, and then select “Write” to send the CV change commands.

General Impressions

I like the heft and feel of the MC II. The throttle knob is very convenient (I dislike using screen-based slider bars for speed control) and is well-integrated with the Engine Driver app. The various buttons on the MC II can be configured for interaction with the Engine Driver app (see here for more details on how). The MC II has the “cool” feature that if you adjust the throttle from Engine Driver’s buttons or slider bars, the throttle knob will automatically rotate appropriately.

Sometimes, you might need to “fiddle” when connecting to the PMA Tx/WCS’s WiFi network. You might even be asked for the password again, but you can usually select “cancel,” and the MC II will connect with its stored password.

Please be very careful with the USB connection on the MC II. Any substantial bending while inserting or removing the USB plug will break loose the USB socket mounted to the circuit board with only two metal tabs – this is a sub-optimal design avoided by most board designers by using four metal tabs to distribute the insertion/removal force and torque.


The video below demonstrates using the ESU MC II to wirelessly control an O-scale SP Cab Forward with a ProMiniAir Receiver onboard.

Demonstration of using the ESU MC II with ProMiniAir Transmitter integrated with a WiFi-equipped EX-CommandStation.


There you have it: another throttle device that can be used with the ProMiniAir Transmitter for radio control of locomotives. The ESU MC II is optimized for model railroading control and provides the superb Engine Driver app for WiFi connection to WiThrottle or DCC-EX servers.

Other throttle devices compatible with the PMA Tx/WCS include any iOS or Android throttle app transmitting WiThrottle or DCC-EX commands via WiFi, the TCS UWT-50 and UWT-100, ProtoThrottle, and JMRI. You can search this website for simple instructions on using these devices for Dead Rail with the PMA Tx/WCS.