Jumper T-Lite Open-TX transmitter

In my journey from building balsa free flight models to getting into radio control, the Jumper T-Lite will be the next step. After deciding to get into RC, I bought some second hand planes and two second hand transmitters, a Turnigy TGY 9X and a Spectrum DX4e. These have been great to learn on, but I want something that I’m going to be able to use for all my models and neither of these is going to cut it.

Enter the Jumper T-Lite.

Jumper T-Lite version screen.

As at 25 May 2021, this is a very new machine. There is a lot of excitement about it in the community, and there are a number of videos on YouTube with reviews and analysis of the machine. A lot of this is focused on quad/drone usage, but even the fixed wing fliers like myself come at it from years of experience and skip over some basic steps.

Of course you would expect this basic information to be “in the manual”, but it’s not. The 4 page “quick start” guide that comes with the T-Lite has one single page of actual instructions which pretty much focus on binding with a receiver, but don’t say what do do with the setup after that. Scroll down for some help with this.

The Open-Tx documentation online is about version 2.2 predating even the 2.3 major release that includes the T-Lite. This is open source software of course, so its not really fair to criticize, but it is important to understand what this all means. It mostly means that to get the most out of this very powerful gadget, you need to find bits and pieces of information all over the internet, including on YouTube, forums and blogs (like this one).

So what I’m going to try to do here is distill what I have found helpful into a bit of a real “Quick Start Guide” that hopefully will help you to get started using it. This isn’t intended to be comprehensive documentation, I hope it helps. It’s helping me to write it!

Initial Setup

Most of the unbox videos you see online cover the basics of turning putting on the antenna (VERY important) and putting the correct 18650 lipo battery (flat top not button top) in the right way round (Positive to the right if you have the T-Lite open in front of you – check this very carefully). These batteries are pretty easy to find, I bought mine from Battery World in Vancouver.

Yes – the USB cable does charge the battery! (but it takes a few hours). You can charge batteries in a separate charger, but you don’t need one. The internal charger won’t overcharge the battery so leave it charging till the light goes off.

Turning on the Transmitter

Things like what comes up first, “Throttle warning” (mode 2). etc.

Using the Keys on the T-Lite

One of the nice things about the T-Lite is the “keypad” – the keys on the receiver. They are labeled, but it’s not really intuitive and apparently the labels rub off over time, so I’ll give you this quick reference table that might help.

Key LabelFunctionUsage/Comments
ENTEnterSelect an item for editing, select an item from a list. Confirm action or entry
RTNReturnNot “return” like on a computer keyboard, this means “return back” to the previous step, or exit out of what you are doing.
UP UpThis one is pretty straight forward, move up a screen, move up a list, move to the previous item when you are selecting options. Sometimes “up” means “up the alphabet”, which intuitively seems to be going backwards because up from “F” is “E” (previous).
DNDownOpposite of UP
SYSSystem or LeftDepending on the context, this button can mean “System” or “Left”. For example when you first turn on the radio you will be in a Model. Press SYS to take you to the main SYStem setup menu for the radio. Once you in the setup menu, MDL and SYS will take you forwards in backwards through the setup pages. Sometimes this can be confusing because you might expect “RTN” to be “go back” but sometimes it might be the SYS button you need to “go left”. So the SYS button will sometimes work as “move left” or “page left”.
MDLModel or RightWhen in a particular model, the MDL button will take you to the model selection screen. But if you are navigating on various screens, the MDL button will usually be a “move right” or “page right”.

Selecting a model

When you turn on the T-Lite you will be “in” the model that you were in last time you used it.

This usually makes sense, the transmitter assumes you want to control/fly the last model you were working with, but If you want to change to a different model or create a new model, press the “MDL” button. This takes you to the model selection screen.

If you are on one of the setup pages for a specific model, you need to press “RTN” first to take you back to the main model screen. Then you can press MDL to get to the model selection screen.

Creating a new model and binding to a receiver

The quickest and simplest way to set up a new model to fly is this:

  1. Get to the model selection screen – usually by pressing MDL from the main model screen or system setup
  2. Move to an empty model slot
  3. Press and hold ENT – this pops up a menu. Use UP/DN to select “Add Model”, press ENT
  4. You are now in a new model – you can change the name now, but its not necessary. You can always change it later.
  5. Press MDL to go to the “Model Setup” page.
  6. Press DN to move down to an empty slot.
  7. Press and hold ENT to popup the menu and select “Create Model”, again using ENT.
  8. Follow the prompts through the wizard. What is weird about the Wizard is that on each page, when you are done with the page you actually press RTN to go to the next page.

New Firmware – should you? Yes now 2.3.14 is good

At this point (25 May 2021), I’d say don’t update the firmware. The version that comes out of the box is good and it works. I flashed a new ‘nightly build’ firmware I downloaded using Open-TX companion and all the gimbals and switches stopped working. I had to “Factory Reset” (see below) in order to get it back from the dead.

But now as at 16 Aug 2021 there is a very clean and solid new “Release” firmware build 2.3.14 that works great and has a couple of but fixes you might want. Like one that stops the battery from draining so fast.

For some reason Open-TX won’t update the firmware from my Mac, so I had to follow the instructions for copying the new firmware to my SD card and booting the radio in boot loader mode. This works just fine.

To start the radio in boot loader mode. Press and hold the two middle trim buttons at the bottom (so the right trim for Rudder and the left trim for ailerons) and then press the power button.

Open-TX companion

The standard Open-TX companion (stable release 2.3.12 or earlier) will not work with the T-Lite as at 25 May 2021. Until Open-TX officially declares 2.3.13 or higher as a new stable release version, T-Lite is not available as an option and you won’t be able to use it with your radio. If you do (I tried) you might even brick it. Recovering is doable but not fun, so just don’t try.

Update as at 24 June 2021 2.3.13 has been released and the Jumper T-Lite is now supported by the Open-TX companion.

One thing to watch out for (maybe only on the Mac), when you first plugin the transmitter to the USB port it can take a long time for the “T-LITE” drive to mount and show up as a device on your Mac. Until it does, Companion will not be able to read or write models. It says it can’t find the radio. Just be patient. Sometimes VERY patient, but it will get there eventually.

Factory Reset

If you are hooped – your transmitter is messed up and nothing seems to be working. You get multiple warnings when you boot and you don’t know what is going on, it might be time for a “Factory Reset”. Luckily this is easy – but its tricky to find. This is how you do it:-

  1. Power off and restart your T-Lite
  2. Press SYS to go to the Radio System menu
  3. Press MDL 5 times to get to the Hardware page.
  4. Press DN to go to the Factory Reset option
  5. Press ENT to select Factory Reset – you are not done yet.
  6. Press ENT again to confirm.
  7. You are done.

Don’t touch the Channel Order

The standard out of the box channel order for the Jumper T-Lite is AETR. Don’t change it.

Also set up the Mixes page to match – for every model. Always do this and never change it:

  • Channel #1 – Ailerons
  • Channel #2 – Elevator
  • Channel #3 – Throttle
  • Channel #4 – Rudder

Always! The only thing you should ever change are the input mixes (e.g. add aileron input into rudder) and rates, and other channels (channel > 4) for flaps, landing gear, 2nd aileron channel – etc.

The multi-protocol module will automatically translate if you use something like a Spectrum/DSMX receiver that expects a different channel order on the receiver. So if you use a DSMX receiver with the channels set as above in the radio, the radio will map the channels when it sends out the signal – so what you will plug in on the plane will be:

  • Channel 1 – ESC
  • Channel 2 – Ailerons
  • Channel 3 – Elevator
  • Channel 4 – Rudder

And you don’t have to do anything! It just works.

If you feel like you want to change to TAER because you a used to it – don’t! If you change it you will break things. If you change the default channel order in the radio or in Open-TX companion, weird things will happen, like the motor running when you move the aileron stick, or your motor just not working. Both of these things happened to me and it wasn’t fun figuring out what was wrong.

[If you are an advanced user you can change this, but you have to use different firmware on your radio – the firmware must be built for the same channel order you select. If you really know what you are doing, follow the information at multi-module.org carefully.]

In short – the channel order for the Jumper T-Lite is AETR (Ailerons = channel #1, Elevator = channel #2, Throttle = channel #3, Rudder = channel #4) – don’t change it.


2 responses to “Jumper T-Lite Open-TX transmitter

  1. I’m having a problem with my quad copter after binding…the controls for aileron and rudder are mixed up. There is a signal for all the control inputs….just not where I need them to be? Please help!

    • It’s very important to understand the difference between Inputs (inputs tab on the radio) and Mixes. There is a lot of good information online and you can look at anything that talks about OpenTX because the Jumper T-Lite is just a smaller version of the OpenTX radio. When you go to OpenTX it talks about the Taranis – that’s a much larger radio, but the screens are very similar. I would always start with Inputs. Make sure the inputs for Roll (Aileron) and Yaw (Rudder) are set on the sticks you want.
      I usually switch these here, as the default just seems wrong. I name the Left stick left-right controller as “Yaw” and the Right stick left-right controller as “Roll”. This matches what you use on your quad and breaks the link to the plane mode. Then go to Mixes and set your AETR (channel 1,2,3,4) to Roll, Yaw, Throttle, Rudder. Hope this helps.

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