Sunday, 27 October 2019

Jumper T16 Pro - is it ready for prime time?

[20 Jan 2020: this review was written before the release of ACCST v2 which fixes a bug affecting detection of invalid data. The MPM devs are working to support v2, but at the time of writing the outcome is not certain.]

The Jumper T16 has been attracting a lot of attention recently - and with good reason as it's well equipped, runs OpenTx, and is aggressively priced. Droners and sport flyers love it... but is it good enough for high value sailplanes? Could it replace my X9D Plus?

There was only one way to find out, which was to get one and play with it!

A bit of personal background: I fly sport and F3F sailplanes, for which OpenTX is - in my view - absolutely unrivaled. For the last six years I've flown with a FrSky X9D and more recently an X9D Plus. Both have been totally reliable and easy to manage - essential qualities for competition work.  In short, the T16 Pro would have to be seriously good to replace them.


The T16’s specification is strikingly similar to the FrSky X10 - they have similar switch layouts, identical screens, and run almost identical variants of OpenTx.

T16 has a same similar spec to X10, but adds an MPM

The big differentiator is the T16's multiprotocol module. This supports more than 50 protocols including ACCST/D16/D8, DSM2, DSMX and HOTT. The module is internal in the 'Pro' version, leaving the external bay free for an additional JR-style module.

Getting it working: JumperTX or OpenTX?

Jumper initially launched the T16 with the JumperTX operating system - essentially a quick and dirty fork of OpenTx 2.2. Unfortunately the JTX data is not compatible with OpenTX Companion, so setups cannot be transferred to/from a PC. Not a good state of affairs!

However, shortly after I received my unit there was a welcome announcement - the T16 Pro would come pre-loaded with OpenTX, with full support from the developers. The next step was a no-brainer - I junked JumperTX and installed a nightly build of OpenTX 2.3.2. Finally, using Companion I copied the models from my X9D Plus to the T16 Pro.

No problems were encountered - all models, F3X templates and Lua scripts work fine.

It works! My F3F setup with adaptive trim script under OTX 2.3.2. Bubbles are from screen protector (my fault!).

Flashing the multi-protocol module (MPM)

The MPM is an open source project by Pascal Langer and is well proven in products such as the iRangeX. It's notably well documented.

With OpenTx installed, my next task was to flash the latest MPM firmware. Normally this would be done by copying the firmware file to the SD card and flashing from OpenTX. However my MPM didn't have a bootloader, so it was necessary to flash the MPM directly. This required a USB to serial adapter, a custom cable, and the installation of flash-multi software on my PC. The procedure is well described here (thanks Benzo99) and I had no problems. A bootloader for the MPM was installed at the same time, so further updates will be easy.

I understand that future MPMs will be shipped with the bootloader already installed.

Using the MPM with FrSky ACCST

Many users will want to pair the T16 Pro with their FrSky receivers. One nice feature is that both EU and non-EU receivers are supported, and I had no problems binding to three receivers, an X8R and RX6R (non-EU), and a G-RX6 (EU-LBT). All worked fine, including telemetry. Note however that the MPM does not support the newer encrypted ACCESS protocol.

Before flying with ACCST for the first time, the MPM's frequency must be calibrated using a FrSky receiver as a reference. The procedure is straightforward, and once the calibration setting is known it can simply be copied into subsequent setups.

The interface between OpenTX and the MPM is well designed - each can be updated independently, and OpenTx will always list the available protocols.

The case 

The case could be straight out of the Futaba catalogue! It’s a good quality moulding with rubberised panels at the side and on the back, and I find it comfortable to hold, though I prefer the slightly chunkier feel of the X9D (I'm a thumber). Unlike the ergonomically challenged X10, I have no difficulty pushing the sticks into the top inner corner.

The carry handle has a thin moulded grip - a nice little detail. The handle itself projects backwards quite a long way, so extra space may be needed in the backpack.

Top view, showing substantial carry handle

Sticks and switches

The gimbals are Hall effect units. Stick length and tension are adjustable. The sticks are very smooth, and there's none of the 'creaky spring' sound which I get on my X9D Plus. However stick feel is marred slightly by a curiously asymmetric feel - I prefer the more progressive action on the X9D.

The layout of the switches is similar to the FrSky X10, except that the 6-position switch is replaced by six illuminated buttons. From a programming perspective they work the same. Like the X10, a couple of extra trimmers are provided (T5 and T6) - great for mix adjusters or auxiliary functions.

Top view showing mini-USB and trainer ports

The only complaint is the side levers - the travel is too short for precise control, there's insufficient friction, and the centre detent is too weak. Some users are attaching felt pads to increase friction.

User interface (OpenTx)

Like the FrSky X10 and X12S, the T16 Pro has a 4.3 inch 480x272 colour display. It also uses the same widget based variant of OpenTX. Unfortunately the default view is almost bare; it shows just the model name (to which you can add a photo), and small icons for RSSI and battery level.

Default screen is a bit bare.

If you want to show some proper info, you have to configure additional widgets, and this can rapidly get tiresome if you have several models. This is not helped by the less than intuitive navigation system.

I have to say that I much prefer the simpler interface on the the X9D. It may not be as pretty, but all the basic info is just a couple of clicks away - and the monochrome panel consumes less power.

To try and improve matters, I’ve written a widget which displays all the basic info in one pane. You can download the widget from here.

My 'show it all' widget

External module bay

The external JR-style module bay adds a lot of flexibility. For example, you can use a protocol such as Crossfire or M-LINK which is not supported by the MPM. Also, by sharing a module between different transmitters, you can swap tx’s without needing to rebind. Or you might just be happier using your favourite module. (Remember that the MPM depends on reverse engineering the official protocols - if you want the real deal, then you must use the appropriate external module.)

Curiously, Jumper skimped on the dimensions - my XJT just module only just fits (after pressing hard), and my M-LINK module refuses to click in place at all. An extra millimeter in depth would have made all the difference.

External module bay with FrSky XJT module

My unit was provided with an empty external module to cover the hole. It looks awkward and rattles, so I made a proper plate for it (downloadable from Thingiverse). I rather like the colour accent from the pink PLA!

Printed module bay cover

The insides

Access to the electronics is easy - just pull off the rubber panels and undo six screws. The internals look neat and tidy.

The switches are soldered to small daughter boards, so there’s no chance of them working loose or being misaligned. On the downside, it  means that swapping out a switch is not a simple task. So if you like the momentary switch on the left hand side (for DLG), this transmitter may not be for you.

Ribbon cables

Almost all the interconnections use ribbon cables. On the plus side, it avoids clutter, however various users on RCGroups have reported misaligned and even reversed connections. Moreover the sockets reportedly lose their effectiveness after a few insertions. I checked out a couple of the cables on my tx (those with more of the blue leader visible), and while the contacts were fine on both, one of them had not been fully inserted into the socket.

Neat innards. Note use of ribbon cables.

Battery and charging

Power is supplied via two 18650 LiIon batteries (not supplied); these fit into a tray which connects to the tx via a short balance lead.

Takes 2 x LiIon 18650 batteries, requires external charger.

To charge the battery, it's necessary to use an external charger which means removing the tray and pulling out the cable. This is a bit of a pain, not helped by the battery hatch being rather stiff. In short, the T16 is crying out for USB charging; in the meantime various aftermarket solutions are available.

In summary

The T16 Pro is a radio of contrasts. On the one hand, it's nicely made, feels comfortable in the hand and comes with adequate gimbals. The multi-protocol module adds great flexibility and appears to works well, on the bench at least.

There are some negatives however. These include: lack of USB charging, rather feeble sliders, inflexible switch layout, and (on some units) poorly assembled ribbon cables. And while the colour screen is undeniably nice, the Horus-style user interface feels cumbersome compared to the X9D.

There is also a question about the operating system: JumperTX looks like a dead end, while OpenTX 2.3.2 is still under development. At the time of writing I do not regard the T16 as flight ready.

Overall, though, it's a thoroughly modern transmitter at a remarkably low price (around £145 at the time of writing). However I would wait until it ships with OpenTx, preferably the production or release candidate version.

Finally, if you wanted to know if the T16 is replacing my X9D Plus... well the answer is probably not. The T16 Pro is more modern, but my old X9D+ still hits the sweet spot with excellent ergonomics and a rock solid version of OpenTx (2.2). Maybe my opinion will change after flight testing - watch this space!

[25 Jan 2020. If you intend to fly with ACCST as your primary protocol, I would hesitate to recommend the T16 Pro or any MPM equipped radio until the situation surrounding ACCST v2 is clarified, from both FrSky and the MPM developers.]


Anonymous said...

I have done a very easy internal charger for it to use the built-in usb. I did it with the old version without internal module, but all that’s needed is to place the charging pcb under the transmitter module.

rumbey said...

Interesting Mike

Im nearly ready to buy this. Probably early 2020 once a few features are sorted

Anonymous said...

Where can we get the widget script "show it all" can you share it?

RC Soar said...

Yes it'll be shared on OpenTX Clinic once it's fully shaken out.

Vladimir said...

Thank you for the MPM bay cover. Nice piece of art... :-)))

William Parker said...

May I please request you to share the Show it all widget as is, for the time being. Just as we use the openTX nightlies would it not be good to keep working with it while you're shaking it out? Honestly I'm being selfish. One look & I simply must have it. It's that good.

RC Soar said...

The Show It All widget is now available from OpenTx Clinic

DaveF said...

I am very interested in using your Showall widget but can't seem to get it working. I am using the Jumper T16 with Opentx 2.3.4,(with LUA selected) and the latest MPM firmware. I have followed your installation and configuration instructions but have hit a brick wall most likely due to my limited knowledge with LUA scripts. When I execute the main .lua file nothing happens. I have also executed the Main.luac file and nothing happens. What is the difference between them? When I select the full screen in the telemetry screen it is blank except for the trim, slider and pot positions. When I select widget setup I don't get the 3 setup options described in your procedure.

Another question I have: what initiates the showall widget when starting up the TX or do you have to execute the program whenever you startup the TX or change models.

Thanks and have a Happy New Year.


RC Soar said...

@DaveF Sounds like you’re not familiar with installing and configuring widgets. It’s a standard procedure, suggest search/post on RCGroups. Once installed and working it’ll appear on an info screen (preferably the first page) when the Tx is powered up.