GreatScott's Radiomaster MT12

[Greatscott]

Now that I have my MT12 in hand, it is time to start learning how to use it. The radio runs on the EdgeTX software, of which I have come to understand, is quite popular in the flying community. With that, I am a complete and total noob. This, if anything, will be a learning journy. Along the way I plan on sharing my perspective as a noob, and sharing good videos and content I have found. My goal here is two-fold, one, learn how to set up the radio, and two, get the most out of it.

Additionally, having used most major brands of radios, I will compare and contrast the differences between those systems and this one.

In the interim, I plan on continuing to use my Spektrum DX6R and DX5C for most of my daily drivers, and use the MT12 for my less pedestrian builds.

The goods:
I bought the ELRS version of the MT12, with a 4N1 module. ELRS gets crazy far range, and the 4N1 will allow me to use some of the RXs I already have. I also bought a battery, and a number of RXs.

Flattening the Curve...
The learning curve for this system is steep for a beginner, but there are few other radio systems that allow the insane about of configuration and customization. As such, I am approaching this system a little differently.

I have made a test board for testing new configurations before they get installed into a RC. This will also give me a test platform for just tinkering and trying different things without actually having a RC to use them in.

I set up to Traxxas ESCs and motors out of a TRX4 and TRX6 as the base. I found two motor mounts on Thingiverse and designed the servo servo mounts, printing the whole mess in PLA.

The big clamps are designed to hold a standard sized servo, holding it securely enough for testing. The small clamps (the bars with ribs) are for mini servos, and for holding things like winch controllers, RXs and cabling. I still need to install a XT60 connector, with a hot lead for the RX's battery monitor. I might just use the power taps on the ESCs, given they come directly off of the battery.

Currently we have been going through a very cold Artic blast, with temps down around -18*f, my shop is VERY cold. Given outside temps in the teens and twenties, my shop normally hovers in the high 40's. I kick on an IR heater and I can normally get my solder bench up to around 60, which is more than enough for soldering. The long and short of it, I will need to wait a few days until the shop warms back up to put the connectors on.

Untitled by Scott O, on Flickr

Untitled by Scott O, on Flickr

[soze]

Awesome, I'll be following this. I'm interested in picking up this radio, but not sure what version yet.

Sent from my SM-G998U using Tapatalk

[Druxus]

Originally Posted by soze

Awesome, I'll be following this. I'm interested in picking up this radio, but not sure what version yet.

Sent from my SM-G998U using Tapatalk

Following as well, very interested in this radio. If I get one it will be the 4 in 1. I'm never that far from my rc so range doesn't do anything for me, but having the possibility of using a bunch of my other receivers is very cool idea. I know the receivers are cheep, but I have allot of rc's that would need a new receiver and the cost adds up quick when you have over 20 rc's.

[cartronicshn]

In for the win...ehh wrong thread, definetly following this thread, i am also looking into a new radio

[JatoTheRipper]

Harley has this radio and seems to love it, but then he tried to make a simple programming change on-air and could not. This radio seems like a major exercise in frustration. Why in the world would they make it so difficult to program?

[Greatscott]

Originally Posted by JatoTheRipper

Harley has this radio and seems to love it, but then he tried to make a simple programming change on-air and could not. This radio seems like a major exercise in frustration. Why in the world would they make it so difficult to program?

The operating system that runs on this radio is very popular in the flying community, but the way you approach the programming is a bit different, and that, I think, is what trips people up who are used to programming the Futabas, Spetrums, and RTR radios.

One big thing is that there are multiple ways to do the same thing. Also, the nomenclature is different. I am just getting into this and share any noob tricks and tips I pick up.

[Greatscott]

Here is the first tip... Fix the channel order.

One of the first things that trips people up right out of the box is the MT12's default channel order: CH1 Throttle, CH2 Steering.
This is something that is native to flyers, but really messes with the minds of us ground pounders. The channels still work the same, but we are used to those two channels being opposite. If you it doesn't bother you, then leave it, but if you it does bother you, or like me, want all of your radios to be the same, then you can change the channel settings in the radio.

• Press the SYS button
• Press PAGE> twice, going to System page 3/7
• Scroll down to Def Chan Order
• Change "TS" to "ST"
--> DONE Now you are set for "One to turn, two to burn".

NOTE: This setting will be carried forward for all new models that are created. Existing models will not reflect this change, and have to be changed manually in the MDL menu for each model. In short, if you want this mod, do it early.

[Greatscott]

Skid Steer Instructions

Having three skid steer RCs, I wanted a better set up for controlling them. I have stick radios, but just like 4WS, my thumbs just cannot agree on what is supposed to be done and when.

The beauty part of this is that you can make a basic setup, them copy it to a new model.

Here is a basic skid steer setup.

Skid Steer Instructions
MDL
Inputs (4/11)
ST Channel -> Long-press, select edit: Change Source to TH
- > Go back to the monitor page and make sure both CH1 & CH2 move with throttle.
MDL
Mixes (5/11)
Select CH1, short click on the roller, and roll down making the mix for that channel.
Repeat for CH2
Go to the CH1 mix, log press the roller, select edit: Source to ST
Go to the CH2 mix, log press the roller, select edit: Source to ST
> Set Weight to “-100”
- > Go back to the monitor page and make sure both CH1 & CH2 move with throttle.

Nope, I did not come up with this, an an awesome YouTuber did (I just wrote it down).

https://www.youtube.com/watch?v=CFwvi5QwInU

[cartronicshn]

NIce, keep them coming, i am saving to get one, i dont feel the controls are going to be a big factor with me, although i am not a pro at flying i´ve been known to crash land several times

[JatoTheRipper]

This could be an awesome guide for MT12 users! Don't make me want one...

[Greatscott]

When you are in a BIND...
Binding ELRS RXs

You can run two types of transmitters, depending on the version and options you get... The 4N1 version of the radio will allow 16 channels, if you get the 4N1 module to go with it, you can have 32 channels (you'd need a supercomputer to remember where you mapped everything). Or, you can get the ELRS version, which allows 16 channels. You can get the 4N1 module for the ELRS version, but you are still capped at 16 channels (which is enough in my book), but it will allow you to use most of the RXs you already have...

Anyhoo... The ELRS version touts longer range, better signal, and faster response, and this is the version I have. Binding RXs is a little different. Whenever you make a new model in the radio, you have to turn the internal transmitter. You do this by going to the model menu, going to Pg2, scrolling down to "Internal RF", and turning it on.

What is a bit annoying is what happens when the Internal RF is off and you go to bind. To Bind an ELRS RX you have to put the RX in bind mode while the RX is off. Then you turn on the radio, go into the System menu, and select option 1, "ExpressLRS". If the Internal RF is on for the current model you have selected, you get into the ELRS menu that has the "Bind" command. If the Internal RF is off you get the word "Loading..." at the top of the screen forever. There is no exit for this, you have to cycle the power to restore the radio. Seems like instead of doing this, the programmers might give you a warning, and an exit. Or... If you the option right there to turn it on... Or... just turn on the Internal RX when you set up the new model.

I know there is an engineering reason behind this, but I can't think of a single case where I would not want that transmitter on. With out it, a radio is just a pistol-gripped brick. With that, I am a noob with this radio... So of the reasons for the "whys" and "hows" have not solidified just yet.

[Gramps]

Just got the 4-in-1 version today.

[Greatscott]

Bind Part Deux... The Receiver (ELRS)

Binding an ELRS RX is a fairly straight forward process, but, as with everything else with this system, it is a little different.
• Turn off the radio
• Turn the RX on three times (on - off, on - off, on)
- The RX will start double blinking
• Turn on the transmitter
• Make sure you have the correct model selected
• Go into the SYS menu
• Select ELRS
• Go to Bind
... Easy Peasy...

Turning the RX on and off repeatedly by pulling and unplugging the RX plug isn't terrible, but not the easiest thing as well. To make this easier I put a switch inline to one of the ESC, making the cycling of power a lot easier.

I wanted a normally closed spring-loaded contact switch, but they only ones I could find at the Ace Hardware were GIANT. We don't have a proper electronics store within a reasonable driving distance. I pulled SPDT switch out of my parts bin and we were in business.

Untitled by Scott O, on Flickr

BIND BLOWN... The RX will stay in TX bind mode for 60 seconds, after that it goes into WIFI mode, where you can log into it with a computer. If you think the radio has an absurd amount of tweaks and geeks you can adjust, the RX has more. But, I have not been brave enough to travel down that road just yet.

I also added wheels to the motors. They allow me to see the motor spinning, and in what direction.

Untitled by Scott O, on Flickr

[Gramps]

Originally Posted by JatoTheRipper

This could be an awesome guide for MT12 users! Don't make me want one...

You know you do. . . . . .

[Greatscott]

Brain droppings...

One thing you need to do to really wrap you head around this radio is to understand that this is a surface radio made by people who understand flight radios. This isn't necessarily a bad thing, but their method of going about things is a bit different than what we ground-pounders are used to.

One of the annoyances of this radio is the fact that you kind of have to trick it to use the 3-position switches on the radio for anything but trims. I am hoping with a little bit of run time, with constructive feedback from the ground community results in a software update that natively allows the use of the trim switches as easily programmable 3-position switches, like we have on the radios we are used to.

Here is a good video on how to use the trip switches as 3-postion switches, and a good illustration of what needs to be changed.

https://www.youtube.com/watch?v=nJDv3AEtwkE

Showing the flexibility of this radio, I figured out a different way to do use the trim buttons as momentary 3-position switches. Basically, I set up a custom curve where the positive and negative curves were almost vertical, needing only one click of the switch to active a servo winch. The video above shows a different, and simpler way of doing it.

[Greatscott]

Common Crawler Controls

Here are some common channel set ups that one might use in a crawler.


Winch Control
MDL
Special Functions (9/11)
T4+ Overr CH3 100 (box checked)
T4- Overr Ch3 -100 (box checked)
Notes:
T4 is the Switch (Trim 4)
CH3 is the RX Channel

On/Off Function (Latching/2-postiion) – Lights on/off
MDL
Logical Switches (8/11)
Edit the first available logical switch (in this case LO1)
Function = Stky (Sticky)
V1 = SC (down arrow)
V2 = SC (down arrow)
Exit
Mixes (5/11)
Go to the channel number (I’m using Ch4)
Edit
Source LO1
Exit

It seems that as powerful as this radio is, the software was designed by someone who didn't understand RC vehicles. It seems like the simplest of tasks are very cumbersome to set up. In my DX6R and DX5C, all of the functionality of the switch is there under one roof. This is a big reason why this will be my "special projects" radio, where I need more flexibility of programming, even it it is at the cost of ease of programming.

My first project will be my Tamiya forklift build. I am using a flight-specific stick radio, and the controls are a bit wonky.

Untitled by Scott O, on Flickr

[Greatscott]

Well, sadly, my first project for this radio kind of turned out to be a bit of a failure.

Control of this forklift was overly twitchy using a stick radio, and I had really hoped the MT12 would smooth that out. The MT12 did smooth the control out a lot, but it also showed that there are big problems with the drive trains in this forklift. Core to my problem, this forklift is just not made to what I am trying to do with it. I need to figure out better tires for it as well. It is still, sadly, a work in progress.

[Greatscott]

A good video on binding Spektrum DSMR RXs, along with the limitations.

https://www.youtube.com/watch?v=KLTIEe_VTGY

Plus binding other RXs

https://www.youtube.com/watch?v=u3wJimmFH2c

[Timmahh]

Originally Posted by Greatscott

A good video on binding Spektrum DSMR RXs, along with the limitations.

https://www.youtube.com/watch?v=KLTIEe_VTGY

Plus binding other RXs

https://www.youtube.com/watch?v=u3wJimmFH2c

Great info Gr8Scott. Thanks much for sharing your brain pickings.

As far as spectrum limitations, anything really serious or troublesome?
I'll watch the vid in a bit, but am interested in how the MT12 works with Speky rxs. Thinking of a better radio system for the LOSI Promoto, which has a few bike specific things on it, mostly the AV6 system built into the rx and adjusting it on the Tx and how compatible it would end up being.

[Greatscott]

Originally Posted by Timmahh

Great info Gr8Scott. Thanks much for sharing your brain pickings.

As far as spectrum limitations, anything really serious or troublesome?
I'll watch the vid in a bit, but am interested in how the MT12 works with Speky rxs. Thinking of a better radio system for the LOSI Promoto, which has a few bike specific things on it, mostly the AV6 system built into the rx and adjusting it on the Tx and how compatible it would end up being.

When using just one RX at a time, the DSMR RXs would fine. When you try to bind more than one to the radio and use the channels collectively, or have both RXs powered up at the same time you run into problems. I could elaborate more, but the second video I linked does a really good job of explaining it.