Sunday, 27 October 2019

Jumper T16 Pro - is it ready for prime time?

[31 Mar 2020: MPM developers announce support for ACCST V2.1]

The Jumper T16 has been attracting a lot of attention recently - hardly surprising as it's well equipped, runs OpenTx, and is aggressively priced. Droners and sport seem to like it... but is it good enough for high value sailplanes? Could it replace my FrSky 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 sailplanes, both for sport and F3F competition. For the last six years I've used 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. Is it? Read on...


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?

My T16 Pro came with JumperTX installed. This is a quick and dirty fork of OpenTx 2.2, and I soon found that it was not compatible with OpenTX Companion. This means that setups could only be typed in directly, and were then effectively marooned. For me, it meant the unit was effectively useless.

Fortunately, the T16 Pro has since gained OpenTX support, and I've now installed OpenTX 2.3.2. Best of all, it plays well with Companion so I was able to copy all the models from my X9D Plus to the new unit. All my models and Lua scripts work fine.

Later units will come with OpenTX preinstalled.

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)

With OpenTx installed and running, it was time to turn my attention to the MPM.  This is based on an open source project by Pascal Langer and is well proven in products such as the iRangeX.

The MPM firmware is regularly updated, so my next task was to install the latest version. Normally this would be done by copying the firmware to the SD card and flashing from OpenTX. However my MPM didn't have a bootloader, which meant that I had to flash the MPM using a USB to serial adapter and a custom cable. The procedure is well described here (thanks Benzo99) and I had no problems. A bootloader was installed as part of the process, and I understand that future MPMs will be shipped with the bootloader pre-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 be copied into subsequent binds.

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. It's quite comfortable to hold, though I prefer the slightly chunkier feel of the X9D. Unlike the ergonomically challenged X10, I have no difficulty pushing the sticks into the top inner corner.

The carry handle incorporates a moulded grip - a nice little detail. However the handle projects back 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 real complaint is the side levers - their 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 TFT display. It also uses the same widget based variant of OpenTX - and suffers from the same deficiencies. In particular, the default view is almost bare; it shows just the model name, plus some icons for RSSI and battery level.

Default screen is a bit bare.

To show more info, you have to add 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 basic info in a single large 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. In particular, it allows you to use a protocol which is not supported by the MPM such as Crossfire or M-LINK. Also, by swapping a module between different transmitters, you can swap tx’s without needing to rebind. Or you might just be happier using the manufacturer's own module (remember that the MPM depends on reverse engineering the official protocols.)

Curiously, Jumper skimped on the module bay 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

To cover the hole, my unit was provided with an empty module case. It looked untidy and rattled, so I made a simple 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 woes

Almost all the interconnections use ribbon cables. On the plus side, it avoids clutter. However there have been a disturbing number of reports of failures causing buttons to behave unexpectedly or not work at all. 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 seem fine, one of the ribbons had not been fully inserted into its 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 yanking 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 designed, and feels comfortable in the hand. The multi-protocol module adds great flexibility and appears to works well.

There are some significant negatives however. These include: awkward battery charging, feeble sliders, inflexible switch layout (DLG flyers beware!), and - most critically - the issues with the ribbon cables. Also, while the colour screen is nice, the Horus-style user interface feels a little cumbersome.

So I guess you want to know whether the T16 Pro is going to replace my X9D Plus. Well the answer is no, at least not for my competition gliders - the older radio still hits the sweet spot with excellent ergonomics, nicer gimbals and a slicker user interface... And most importantly, it has a bunch of proper connectors instead of those pesky ribbon cables.

In the meantime, watch out for the forthcoming Radiomaster TX16S. It sounds like a more developed knock off of the T16 Pro, and should address at least some of the issues identified in this review.


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.