There are several more switches on the front panel. At the upper right is one identified as "AIL/ELEV D/R." It simultaneously turns on or off dual rate control for the aileron/elevator (or rudder/elevator for three-channel control). This switch also turns on/off the special exponential rate control to the same two channel functions. 

At the top left corner of the case is a momentary contact (spring return) switch to operate the trainer-cable function. The "From the Ground Up" installment in the September 2003 issue (on page 71) has a more detailed discussion about using a trainer cable.

When momentarily pulled forward and released, that trainer-cable switch will act as an engine-kill (stop) switch. This is helpful when your transmitter employs digital trim, as does the T6EXA. By pulling this switch, you don't have to operate the throttle digital trim lever to completely kill your glow-fueled engine. (Frank Granelli will explain this in more depth later in this series.)

We've finally gotten to the computer system. At the lower portion (middle) of the transmitter case is an LCD screen. To the left of the screen are two push-button switches identified as "MODE" and "SELECT." To the right is a data-input switch that moves up (+) and down (-). Next to this switch the six channel controls are listed by number and function, such as "CH1=Aileron," "CH2=Elevator," etc.

When you first turn on the transmitter power, an initial or basic display will appear on the LCD screen. It will have a small number (1 through 6) at the upper right and a larger number, such as 10.0v, at the lower right. The smaller number tells you which computer-memory position is currently in operation. 

The larger number is this particular transmitter's battery voltage. At 10.0 volts or slightly higher, the transmitter battery is close to full charge. When the voltage falls to 8.5, an audible alarm will sound and a battery icon will flash on the LCD screen. This is a warning to land your model immediately because you only have several minutes of charge remaining. At that point you recharge the battery or substitute a freshly charged battery pack.

To access the various control features, you must get into the T6EXA computer menu. Many of these computer radios have two menus; one is for basic programming and selection of the model memory and the other contains all of the detailed control features. I chose the T6EXA because it only has one menu, which makes it simple.

With the transmitter power on, press the MODE and SELECT switches (keys) and hold them for a second or two. The first thing to show up on the LCD screen is the "MODEL" memory position. A large-size number (1 through 6) will flash on the screen. You change the model number by pressing the data-input (+ or -) switch. This will allow you to scroll up to 6 or down to 1.

On some computer transmitters you can add a model's name to the memory-position number for identification purposes, but that feature isn't available on this unit. As an alternative I pasted a list on the rear of the case indicating each model and the number assigned to it.

You must be especially careful when selecting the correct model-memory position. If you don't select the right number, you may find your controls reversed and a crash could easily result. On the other hand, remember that you can operate as many as six different aircraft from this transmitter.

While still in the MODEL portion of the menu, if you press SELECT you will see a "CL" flash on the LCD screen along with the model memory-position number. Pressing either data-input key (+ or -) for roughly two seconds will erase any inputs stored in that memory position. Controls will then be restored to factory-default settings. This can be helpful when you are setting up controls for a new model.