|Futaba T14SG: 2.4GHz transmitter,|
12+2 channels and telemetry.
3. I've replaced the programmable mix that I used for dual rate functionality with the intrinsic dual rate function that comes with the T14SG in its firmware. I've crossed-out the corresponding text and added a link to how to program dual rate.
2. Switch SH that resets flight timers T1 and T2 needs to be wired with RESET and not STOP. The screenshots are correct, though.
1. The text now properly reflects programming for the S.BUS2 setup.
Some YouTube videos made me think that I could manage the task of replacing the receiver and programming my Futaba T14SG transmitter. However, I opted for writing instead of filming how to program the transmitter as I find writing more suitable for this particular task. You can take your own pace when working through this tutorial without having to stop a film and rewind all the time.
How to Programm?
RC model gearheads are a flock of their own. While we finally see computer technology getting introduced also in this field, some things are still rather awkward. At least, with the more capable transmitters we can now backup our transmitter settings on SD card. But an easy documentation is still lacking ... the files on SD card are not suitable for understanding what is going on and are thus useless when you need to transfer the programming shown here to another transmitter type. So we are back at photographing LCD screen. Beautiful new technology...
But don't be afraid, this isn't going to be picture guessing. Along with the LCD screenshots I will also explain what I'm doing here. I'm sure this is a real bonus compared to simply offering a file for download that is only usable on a single type of transmitter.
Programming the Phantom
In case you purchased your T14SG with a LiPo battery, you first need to deal with the transmitter itself. To be particular, we need to properly set the warning level for the transmitter battery in this case. The default warning voltage is not suitable and must be changed in order to avoid mishaps.
T14SG Battery Warning
While the T14SG manual warns to set up the battery warning properly you are left wondering where to find the instructions to do so...
To answer my little test: the chapter is titled Warning and can be found somewhere in the middle of the manual. And the corresponding setup screen is located inside the Linkage menu. Completely illogical, isn't it? Maybe you need to be an old RC model gearhead to understand or at least accept such design. What about hiring a real document author that is worth her/his money? Oh, I forgot: no money, right?
|Don't forget to adjust the battery warning level!|
Then tap on [S1] to switch to the second page inside the Linkage menu. There you will find the menu item [WARNING]. Scroll to it using the touch field, then tap [RTN] in the center of the touch field.
|LiPo 2s warning.|
This warning ensures that your transmitter does not run out of juice unnoticed so you don't loose control of your RC model.
With this out of the way let us now focus on the main task: programming your transmitter for flying a Phantom.
Only One Single Cable: S.BUS2
|Simple wiring using S.BUS2: DJI calls this D-Bus instead.|
Configuring the Phantom Modell
|The fun starts here: MODEL SEL(ection).|
For reasons I will never, ever understand, Futaba puts Model management, such as creating, deleting a model, et cetera into the model selection item inside the linkage main menu. For the German-speaking RC enthusiats they are even topping this be calling the linkage menu the basis menu instead. Alas, quickly tap twice on the [LNK] field in the touch field to enter the linkage menu.
Next, go to [MODEL SEL.] and tap [RTN]. In this configuration screen we can either activate an existing model or create a new one. Actually, Futaba calls copying a model for another unknown reason creating a new model from an existing one. Well, I won't ever understand the trains of thought that seem to be typical to RC model vendors.
|Create the Phantom as an airplane.|
Really? An airplane model? This surely is a quadcopter!
That's correct. The reason is that the Naza-M flight controller needs its steering signals separately, very similar to what an airplane model needs. It can't handle the partly mixed signals that a helicopter requires.
Next, we want to give our new model a name. Space is tight, so we have to get away with whooping ten characters. For instance, «DJIPhantom» perfectly fits into the available space. When the name is set, the T14SG automatically switches to the [MODEL TYPE] configuration screen. This screen is about different types of airplane models.
|I'm a happy Phantom airplane ... for sure!|
For whatever reason, the RC transmitter vendors still don't know about multi rotor model in ther highly sophisticated computer transmitters. Not that such models have just appeared on the market...
|12 channels are enough.|
But back to our Phantom equipped with the Futaba R7008SB receiver: for our purposes, 12 channels are more than enough. To be precise, these are only 10 servo channels and two additional on/off channels. But in marketing, 12 is better than 10 so they put it prominently on the box. Like class 10 microSD cards...
As we are interested in seeing the current flight battery voltage while in flight, we need a radio link type that has the telemetry function. But since we only need the builtin telemetry base function, we better go with the link mode [FASSTest 12 CH]. This reduces control latencies as there is only a tiny data packet to be sent back to the T14SG, so cycle times are kept small for terminal-to-terminal control ... ops, wrong movie. There is also a FASSTest 14 channel link mode available which only comes into play if you either really need that amount of channels or have additional telemetry gear attached.
As battery voltages will only slowly change over time, we then set the donwlink cycle to once per second: [1.0s] (in the row marked «ACT»). This won't hurt the battery consumption noticeably as there will be only a short chirp.
Please note that in the Phantom the receiver voltage is stabilized (this is done in the PMU, the power management unit). So unless the flight battery voltage drops under this level you don't get any valuable information. But if it does, your Phantom will already have fallen out of the sky by then. For this reason, a battery failsafe is also of no use, so we leave this setting as is. Instead, we will later set up a low flight battery warning in the T14SG transmitter.
Down is the New Up...
|Reversing the right channels.|
For our Phantom we need to reverse the directions for the following channels: channel 2 «ELE» and 3 «THR», as well as channel 6 «AUX2» and 7 «AUX3». Make sure that these channels are set to [REV]. All other channels must not be reversed and thus set to [NORM].
We need to reverse channels 6 (AUX2) and 7 (AUX3) as otherwise the switch positions of the T14SG switches for flight mode and IOC would be the reverse of what we have learnt from the DJI transmitter. Keeping things the same will avoid making silly mistakes when flying.
Next, we need to wire up some switches, in particular, switches for channels 6 and 7. These channels instruct the Naza-M flight controller in which modes to operate: channel 7 (AUX3, or U at the Naza-M) controls the flight mode, while channel 6 (AUX2 or X2) controls IOC. We also wire up the slide lever to channel 5 (AUX1 or X1) which later will be picked up by the gimbal.
|Wire up your switches.|
- we assign control of the flight modes (that is, GPS, ATTI and optionally MAN) to the right switch «SC» of the T14SG. This switch has three positions and its position is similar to the same switch on the DJI transmitter. So, connect channel 7 [AUX3] with switch [SC] (under column header «CTRL»).
- similar, we assign the IOC to the left switch «SB» of the T14SG. Again, we use a three-position switch that is located on the T14SG similar to the position of the same switch on the original DJI tranmitter. Thus, connect channel 6 [AUX2] with switch [SB].
- Finally, connect channel 5 [AUX1] with the left slide lever. It is called [LS]. Depending on your preferences, you may want to use the right slide lever or one of the two volume rotary knobs on the front of the T14SG.
This is the End! Count to 10, ...
Luckily, we only need to tune channels 6 and 7, all other channels are unaffected. So, in the linkage menu, go to [END POINT]. Skip the first page, as its settings are correct.
|Endlagen für Flugmodus und IOC.|
In principle, we could also use a mixer, but this would be too much effort to what obviosly can be done much simpler. Just adjust the end points and you're done. Leave all other end point setting for channels other than 6 and 7 intact, that is, at 100%.
This display shows in realtime the channel values that the T14SG transmits over the air while you pull your control sticks and toggle switches. You may want to control servo directions as well as end points using this convenient display. There is one gotcha, however: Futaba displays a channel value of -100 as going up instead of down. Another RC model idiosyncrasy, me thinks.
- when to pull the throttle stick completely all way down to you, channel 3 must be at -100%.
- channel 7 must take on these three values, according to the following positions of switch SC, kontrolling the fligth mode: top position (GPS) must yield +80%, middle position (ATTI) must yield 0%, bottom position must yield -80%.
- Similar values must be yielded for the IOC switch SB for channel 6: top position at +80% and bottom position at -80%.
The second timer T2 acts as a come-back reminder. T2 starts at 5 minutes when you push the throttle stick for the first time, counting down. When T2 reaches zero it beeps to remind me to come back.
In order to reset both T1 and T2 we will wire up them to button SH. This switch is spring-loaded so it always snaps back to its off position.
With the telemetry function for the flight battery voltage wired up and working the timers are now of much less importance. However, they are still a nice additional function so I'm leaving them in and describe here how to set them up.
Flight Duration T1
|Timer T1: flight duration.|
To set up T1 first go to the main screen. There, use the touch field to select [T1] and then tap on [RTN]. You will now see a timer configuration page as shown in the figure to the right.
Timer mode is [UP]. The alarm, which is rather a reminder, should sound at 10:00 minutes, so set this value using the touch field next to alarm.
|Key SH resets the timer.|
|Pushing the throttle stick starts the timer.|
The flight duration timer T1 is now set up.
Come-Back Reminder T2
All other settings for [START] and [RESET] are those as of timer T1.
|Telemetry data for the battery voltages.|
|Live flight battery voltage reading!|
|Only show the flight battery voltage, nothing else!|
For SENSOR now select «----------». This is Futaba's notion for Nothing. Acknowledge with [RTN] and the setup screen will be updated with the only remaining data set for EXT-VOLT. Don't remove this one, as this is the one we want to display.
When you now return to the telemetry screen it will only display the external voltage, which in fact is the voltage of the Phantom's flight battery. Sweet and useful!
This is an ugly topic. The reason is that we have roughly three levels of failsafe functionality. And cascading them in general is a bad idea. I'll describe the setup of the T14SG/R7008SB in the context of a Naza-M flight controller in a separate article. Stay tuned. Okay, here it is: T14SG and the Phantom Failsafe.
A Little Help
If you like, you may want to throw in a little flight aid that reduces the rudder stick amplitude.
Note: Alternatively, you may want to use the built-in DUAL RATE functionality instead that comes with the T14SG. It's no big deal to set it up to your needs.
|Check that all channels are working correctly, as well as|
Power on the T14SG, then power on the Phantom, connect it to your Naza-M assistent using a working USB cable. At this time, your Phantom will rapidly blink yellow, as it entered failsafe mode because it doesn't receive any valid command. Remember that it is still in PPM mode, no S.BUS operation yet.
If not already done so, you first need to upgrade the Phantom's firmware inside the Naza-M up to version 3.16 or later. This is the first firmware to support S.BUS2. After upgrade, follow the instructions to reset and reload the correct default values into the Naza-M.
Next, in the Naza-M assistant sofware go to page «Basic» and select tab «RC» there. Select D-Bus as the correct receiver type. Don't forget to recalibrate now.
Important: As you are now using a (new and) different transmitter and receiver you have to calibrate in order to correctly have the Naza-M learn the neutral positions and maximum channel values. Use the buttons labelled START, next to the word Calibration.
Absolutely make sure that the Naza-M correctly detects all switch positions for channel U (which controls the flight mode) and channel X2 (which controls the IOC). Also check failsafe operation, if you have followed my example on setting up mixer 2 (described in T14SG and the Phantom Failsafe). Flip switch SG, then you should see channel U jumping into a failsafe position.
If something does not work as expected, check your programming of the T14SG.
Only after you have thoroughly checked that everything works as expected you are ready to go on a field and to a field test (in the true sense of the meaning). Grab your fully-charged batteries, your transmitter, and your Phantom and off you go. Enjoy your flights!