Radiomaster MT12 - Review and Guide

[WickedFog]

Introduction

@Lostinthewoods86 sent me this radio for scientific purposes. So as I learn more about it I am going to use this thread to document things I figure out with this amazing radio.

Here is everything you get, and currently, you can grab this radio for around $130 from various online shops and retailers, as well as Amazon.

​

Description​

The RadioMaster MT12 is a pioneering open-source surface radio, and the first surface radio officially supported by EdgeTX, ExpressLRS, and the Multi-module project. Boasting 10 physical inputs and the capability to handle either 16 or 32 channels*, the MT12 is primed for a wide array of surface models, from cars and trucks to boats and beyond. Featuring extensive customizability and a versatile operating system, the MT12 stands out as a highly configurable surface radio, prepared to excel in virtually any scenario.


Features

• Available with Built-in ExpressLRS Backpack or 4in1 MPM RF modules
• Featuring a powerful STM32F407VGT6 with 1MB Flash
• Preinstalled EdgeTX firmware
• QC3.0 fast charging supporting 2.0A MAX
• Compact design with excellent ergonomics
• Oversized battery compartment - 2 x 18650 cells or a 2s 7.4v 5000mah battery pack (Batteries not included)
• Standard Nano module compartment
• RadioMaster standardized button layout
• Rotatable antenna
• Customizable base switches or 4 way joystick included

 Specifications

• Item: MT12 Surface Radio
• Physical dimensions: 177.8*118.4*207.8mm
• Weight: 480 grams
• Operating frequency: 2.400GHz-2.480GHz
• Internal RF Options: 4-in-1 multi-protocol / ELRS 2.4GHz
• Supported protocols: Module dependent
• Operational current: 160mA for 4in1 / 320mA for ELRS
• Operational voltage: DC 6.6-8.4V
• Operating system: EdgeTX
• Control channels: 16 as standard, ability for expansion 32 Channels (4in1 only)
• Display: 128*64 Monochrome LCD
• Battery: 2 x 18650 cells or a 2s 7.4v 5000mah battery pack (Batteries not included)
• Charging: Built in USB-C Charging
• Firmware Upgrade method: Via USB or SD card
• Wheel and Trigger sensor: Hall-effect
• Module bay: Nano size (RadioMaster Ranger Nano Module / RadioMaster RM 4in1 module / TBS Crossfire Nano module)

*32 channels requires a 4in1 radio and additional 4in1 RF module along with compatible receivers

Specifications for ER3C-i (Included with ExpressLRS version)

• Item: ER3C-i 2.4GHz ELRS PWM Receiver
• Power supply: DC 4.5 - 8.4V
• Antenna type: Built-in high-sensitivity ceramic antenna
• Wireless protocol: ExpressLRS 3.3.0 pre-installed
• Output channel: 3CH PWM
• Telemetry power: 10mW
• Battery voltage detection range: DC 4.0 - 35V
• Weight: 4.2 grams
• Dimensions: 26.1*18.5*13.0 mm
• Firmware: Device Category: Radiomaster 2.4Ghz / Device: RadioMaster ER3C-i

Specifications for R85C (Included with 4in1 version)

• Item: R85C Receiver
• Power supply: DC 4.5 - 8.4V
• Frequency range: 2400-2483.5Mhz
• Support protocol: D8/D16/SFHSS
• Output channel: 5CH PWM
• Antenna type: high-sensitivity 2.4G antenna
• Telemetry power: 100mw / 20dbm
• Weight: 5.7 grams
• Dimensions: 31.0*18.5*13.0 mm

EdgeTX Operating System
Preinstalled with EdgeTX, the MT12 has cutting edge software fit for its class-leading hardware. RadioMaster works closely with the EdgeTX team to develop new features and optimize the user experience for surface models. We will continue to contribute and support projects like EdgeTX, ensuring the concepts of open standards are carried forward.
For more information, please visit https://edgetx.org/

Available with ExpressLRS and 4in1 Version
In addition to the popular internal 4-in-1 Multi-module, the MT12 is also available with an internal 2.4GHz ExpressLRS (ELRS) module. Designed to provide reliable long-distance control, super low latency, and high refresh rates. ELRS is a revolutionary open-source protocol taking the R/C industry by storm.

ExpressLRS Version
ExpressLRS supports ultra-fast response modes for seat of your pants racing or super long range modes for pushing the limits of your adventures.

4in1 VERSION
One remote to control all of your cars. The 4in1 internal RF system has protocols, for many popular brands of cars and receivers.
Click here to visit the list of supported protocols

For some quick tips when you first get your radio, you can check out some of Radiomaster's videos here:
https://youtube.com/playlist?list=PL_iw2u3UZ8R2aJE5DHvJXBh6vn-yl6Pi-&si=8sM4q7t_6vmt6pvg

Before You Buy
There are two options for this radio. The ELRS version, and the 4in1 version.

The ELRS version is for use with ELRS receivers. This protocol is designed to provide reliable long-distance control, super low latency, and high refresh rates. Great for racing applications.

The 4in1 version of the radio has an included module which uses the most popular protocols for today's RC radio systems. The 4in1 version will bind with Traxxas, Spektrum, Flysky, and many other brands of radio system protocols, meaning you can use this version to control nearly all of your RC's, without having to swap out the receivers.

If you buy the ELRS version, you can also grab the 4in1 module which will attach to the module port on top of the radio.

This will allow you to choose between the ELRS module, or the attached 4in1 module to have the best both versions of this radio has to offer. However, with the ELRS version of this radio, you will be limited to only 16 channels. With the 4in1 version of the radio and an additional 4in1 module, you can pump this radio up to 32 channels. Why anyone would even need 16 channels on a surface radio is beyond me, but OK.

If you buy the 4in1 version, you can also buy ELRS modules to take advantage of the improved range, low latency, higher refresh rates, etc.

If you want to read up on any other info about this radio you can check it out on Radiomaster's website located at:
www.radiomasterrc.com

 

[WickedFog]

Unboxing

This arrived yesterday, so let the learning begin.

Comes with a nice case, some stickers, and a manual.

1st side of case.

2nd side just has a box of goodies.

Inside the box is a screen protector, USB cable, module adapter, R85C 5 channel receiver, 4-way joystick expansion module, dual switch expansion module, and a pretty nice leather lanyard.

 

[WickedFog]

First impressions

This radio feels like a fairly high quality unit. It doesn't feel cheap at all like regular RTR radios, or the budget friendly options out there.

Opening up the battery tray I was happy to see this actually comes with an 18650 battery holder, so you can use individual 18650's in it as well as the 2s 21700 battery packs. The 21700 battery packs will provide more mAh than you can get with the individual 18650 batteries, so you will get more run time from the 21700 packs. Individual 18650's max at around 3600 mAh. 21700's max out at about 5000 mAh.

The JST port on the left is where the battery pack/tray plugs in. The empty port in the handle area is where the expansion modules plug in.

I decided to use the dual switch module. These switches can be setup as light switches, can be used to toggle driving modes, etc.

Module plugged in

Now we have two more switches to use

The buttons, knobs, and switches on this radio feel really nice and clicky, and not at all cheap. The trigger feely silky smooth, as does the steering knob, which both use hall effect sensors, so there is nothing to really wear out on the controls. The trigger is adjustable and can slide forwards and backwards. You can also adjust the spring tension.

My only complaint about the ergonomics is the two buttons and one trim switch by the thumb are all kinda difficult to get to. Other than that the radio feels comfortable in my hand.

For what this radio sells for, you really do get a lot of radio for the money. The overall look and feel of this radio gets a lot of compliments where people are surprised at how nice the radio looks and feels.

 

[WickedFog]

Upgrading the Firmware

READ: Do NOT plug your radio into your computer until instructed to do so. Your computer will likely install the incorrect driver, and you will have to remove that device from the device manager on your pc for the correct driver to install.


Getting Your PC Ready - DO THIS FIRST
BEFORE trying to update your Radiomaster MT12 or even plug it into your PC, I would suggest you download this software so your PC has the correct drivers to talk to the radio:
https://www.st.com/en/development-tools/stm32cubeprog.html
You will need to create an account and log in before downloading the software.

Scroll down to this section of the page and select the proper file for your PC. If running Windows, you will want the last file...

If that is too much trouble, you can grab the Windows 64 bit file directly from my drive here:
https://drive.google.com/file/d/1CTfVTCH6WxnLKIlJMrPeK3G1C12KSgT-/view?usp=drivesdk

Download that and run it. Just follow through the prompts to install it. Restart your computer.


Backup Your SD Card in the Radio
NOTE: There are two USB Type C ports on the MT12. The one at the "heel" or back of the base of the radio, just above a button labeled "SD", is ONLY for charging your battery pack.

To access the radio and SD card you need to use the USB port under the rubber cover on the left side of your radio. See pic below.

Before updating your firmware, you want to backup the contents of your SD card on the radio. To do this, turn your radio on and let it boot up. Then connect the included USB cable to your radio (remember, use the USB port on the left side of your radio) and plug it into your computer. You will see a popup on the radio to 'Select Mode'. Select the option 'USB Storage (SD)'.

Then on your computer you'll want to open your PC window where your drives are and look for your radio. Open that and select all the folders/files to highlight them and copy them to a backup folder on your computer somewhere. I suggest you make an MT12 folder in your documents folder to store all your files for this radio. You will likely accumulate more. Create a Backup folder inside that folder and stick your radio SD card backup in there.

READ: Turn the radio off and unplug it from the PC. You will be plugging it back in.


Upgrading Your Firmware
After you have the STM software installed, the SD card contents are backed up, with the RADIO OFF, plug it back in to the PC. Your PC should go bing-bong confirming the radio is plugged in. Then click the link below to go to the EdgeTX site to update your radio's firmware to the latest version.
https://buddy.edgetx.org/#/flash?version=v2.10.4

On the next page there will be a panel on the left to select the firmware version and your radio. You'll want the latest version, unless you are rolling back to an older firmware.

On the next page you You'll need to click 'Add new device'.

A window will pop up. Select 'SMT32 BOOTLOADER' from the list and click 'Connect'

You should then see 'SMT32 BOOTLOADER' in the list of devices. Select it and click 'Next'.

Simply click 'Start Flashing' to flash your firmware.

And you're done!

 

[WickedFog]

Radiomaster has released some additional sensors to add on to their compatible CRSF telemetry equipped receivers. These sensors add additionale telemetry options to their already powerful line of ELRS recievers.
These sensors are available here:
https://radiomasterrc.com/collections/ers-series-sensor


These sensors require the following software:

• EdgeTX 2.11.0 or later versions
• ExpressLRS 3.6.2 or later versions

Compatible with the following CRSF Plug and Play equipped Receivers:

• ER6 2.4GHz ExpressLRSPWM Receiver
• ER8 2.4GHz ExpressLRSPWM Receiver
• ER8G ExpressLRSPWM Receiver
• ER8GV ExpressLRSPWM Receiver

Current sensor addons include:

• Precision GPS
• Precision cell voltage sensor (1-8s)
• Real-time current sensor (1-150A)
• Brushless moto tachometer
• Gas engine tachometer
• Barometric altitude sensor

Each of these sensors have and additional external CRSF port to daisy-chain additional sensors together.

 

[WickedFog]

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[WickedFog]

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[Greywolf74]

Guess i know what I'm doing tomorrow! lol

 

[CertifiedMike]

This is AWESOME!!!
Thanks for going into detail on this!
all the info!!!
Good luck with this beast!
32 channels!!! SMH!!!

 

[WickedFog]

This is AWESOME!!!
Thanks for going into detail on this!
all the info!!!
Good luck with this beast!
32 channels!!! SMH!!!

It will take me a bit of time to start diving into this radio, but I am going to add what I can as I go. I have played with it a bit, and I can say this is the nicest radio I've had for surface stuff. It's a bit to wrap your head around with all the settings this radio has, but you can use it as is and play with that stuff as you go. It's a radio you can customize the hell out of basically.

For example:
The model button takes you to another page. And there are 12 pages (different screens you can page to) of settings and info there.

Pressing the System button has 7 pages of settings and such.

And inside those pages, the settings themselves have their own pages of settings.

There are a ton of variables you can key in that do different things. And tying these variables together through global settings, logical switches, and special functions can turn this radio into a completely different animal with the flip of a switch, or by selecting a different model from the memory.

Want a radio setup for rock crawling? This one will blow your mind with the 4 wheel steering setups you can do with this. Drag car setup? Yup. It has a lot of settings that will handle throttle curves, throttle weight (max throttle limiter), brake weight, etc. And you can toggle between a tire warm up routine, to a staging routine, to launch mode with the flip of a switch. I don't really see an end to the possibilities with the EdgeTx firmware on this radio.

 

[CertifiedMike]

It will take me a bit of time to start diving into this radio, but I am going to add what I can as I go. I have played with it a bit, and I can say this is the nicest radio I've had for surface stuff. It's a bit to wrap your head around with all the settings this radio has, but you can use it as is and play with that stuff as you go. It's a radio you can customize the hell out of basically.

For example:
The model button takes You to another page. And there are 12 pages (different screens you can page to) of settings and info there.

Pressing the System button has 7 pages of settings and such.

And inside those pages, the settings themselves have their own pages of settings.

There are a ton of variables you can key in that do different things. And tying these variables together through global settings, logical switches, and special functions can turn this radio into a completely different animal with the flip of a switch, or by selecting a different model from the memory.

Want a radio setup for rock crawling? This one will blow your mind with the 4 wheel steering setups you can do with this. Drag car setup? Yup. It has a lot of settings that will handle throttle curves, throttle weight (max throttle limiter), brake weight, etc. And you can toggle between a tire warm up routine, to a staging routine, to launch mode with the flip of a switch. I don't really see an end to the possibilities with the EdgeTx firmware on this radio.

I have already watched some vids about how to do programming! What a cool radio!
Bardwell has a vid about these that I found comical. I think it was the timer feature that he called stupid and outdated. Anyway, whatever feature, his video was pretty informative and easy to follow.
I have to draw lines though. I trust you to give an unbiased opinion more than I do someone who gets paid in r/c land. That's just life, nothing against anyone!

This radio, even at 16 channels (Molly Ringwold just popped into my head there ) is likely more than I could ever see myself using.
Even if I installed each of them myself, I'd have forgotten half by the time I'd finished the 16th channel leds!
5 channels seems sufficient.

 

[WickedFog]

I have already watched some vids about how to do programming! What a cool radio!
Bardwell has a vid about these that I found comical. I think it was the timer feature that he called stupid and outdated. Anyway, whatever feature, his video was pretty informative and easy to follow.
I have to draw lines though. I trust you to give an unbiased opinion more than I do someone who gets paid in r/c land. That's just life, nothing against anyone!

This radio, even at 16 channels (Molly Ringwold just popped into my head there ) is likely more than I could ever see myself using.
Even if I installed each of them myself, I'd have forgotten half by the time I'd finished the 16th channel leds!
5 channels seems sufficient.

I expect this EdgeTx firmware to spawn other radios that use it. If so, there could be some really cool things to come from this.

 

[CertifiedMike]

I am so close to pulling this trigger!!!

 

[WickedFog]

I am so close to pulling this trigger!!!

I'm pulling the trigger right now. It's not doing anything though. I need to connect it to an RC first I guess

 

[CertifiedMike]

Yeah yeah, rub it in why don't you?!

You know, if you weren't picking on all of us right now, you COULD be installing that receiver... Just sayin...

 

[WickedFog]

Yeah yeah, rub it in why don't you?!

You know, if you weren't picking on all of us right now, you COULD be installing that receiver... Just sayin...

Yeah, I need to connect it to a few of my RC's. My kiddo will be here Friday, so I'm planning on doing some binding this weekend to see how that process is.

 

[CertifiedMike]

Yeah, I'd like to hear about how that goes.
@PainKiller asked about an upgraded radio and I think THIS might solve a few issues.
It does have a steep learning curve but he SEEMS a smart fellow... we shall see...
If this radio binds with rtr's so we have our "good" radio to use if we choose BUT if the neices and nephews might be over and bored and looking to bash, the SLT2 and 3 will be perfect and minimal loss if they get bashed up too!

 

[WickedFog]

Just ran across this while doing some learning. Pretty good explanation of what this radio can do. He has a lot of cool vids on the MT12.

 

[Robert Droner]

lol, Painless 360 (Lee) has been at this stuff for many years and is a great go to guy for this kind of info. This radio is a great radio. I use it with a Crossfire module on an xmaxx 8s. You wont get a loss of signal with this thing!

 

[WickedFog]

lol, Painless 360 (Lee) has been at this stuff for many years and is a great go to guy for this kind of info. This radio is a great radio. I use it with a Crossfire module on an xmaxx 8s. You wont get a loss of signal with this thing!

I have been watching his videos all day. He has some really good ones.