900Mhz Mavlink modules?

General
1

900mhz Matek mLRS
VS
900mhz Mavlink ELRS
VS
900mhz Mavlink over TBS Crossfire

The ELRS website advises against using 900Mhz for Mavlink due to slow telemetry link, but Matek has a 900Mhz mLRS module and people have reported fantastic range, reliability and speed with them? Why is that? Also is Mavlink over TBS 900Mhz poo poo compared to Mavlink ELRS?

I’m using TBS Micro TX V2 and Nano RX Pro and I want to be able to upload mission mid flight, doing ROI, point here, fly here and all that good ardu stuffs inside a 10KM radius. Can it do that or I’m better off just buying the Matek mLRS?

2

Apples.

Oranges.

Bananas.

Not all 900 MHz setups are the same, so the advice given on the ELRS website is accurate, but no even for all of their configurations.

First, Mavlink over TBS Crossfire. That’s easy: Don’t. It was a great idea but the implementation just never matured. Unless you have a work bench full of TBS Crossfire gear you’re itching to play with, don’t bother with this one. Certianly don’t buy anything specifically to do it. I had it work on the bench, okay-ish, but in the field it was just junk and never had anything I’d call useable.

mLRS: It is solid, and works really well. I’ve had amazing range from really low power hardware in less than ideal conditions. But, it’s purpose built and not the most user friendly for setup with new users. They are working to make it better. If you’re only planning to use your hardware for Mavlink devices this is a choice. Once it’s setup it will be great, but you’re going to need to get into the weeds. I haven’t used the specific Matek mLRS hardware, but I suspect it would live up to the standard.

Mavlink over ELRS: It’s got way better with 4.0. Probably the most user accessable. But, the hardware matters. If you’re going to use 900MHz then for best performance you need to be using a TX and RX with the new LR1121 chipsets. That will give you access to the modes that will give the best perforamce. The warning about 900MHz is relating to the older chipsets. With the older chips the 900MHz performance is not useable.

I really liked mLRS, but I wanted to use my hardware with things other than Mavlink, so when ELRS 4.0 came out I switched back. I use the RM Nomad with the RM XR4 receivers. Mostly on 900MHz, but I do have one on 2.4GHz. Life has been such I haven’t been able to really push the system, but everything I’ve tested so far has been uneventfull. YMMV.

3

I also use Mavlink over ELRS 4.0. I use the RM XR4 receiver with the RadioMaster GX12. I really like being able to use the receiver for both the RC signal and data. I don’t have any complaints about using Mavlink over ELRS.

4

Not trying to hijack the thread, but I’ll add strawberries as another option. :laughing:

They’re a bit more expensive, but I can easily recommend RFDesigns’ RFD900-series modems and their TXMOD.

I use their RFD900ux’s.

Long range 900 MHz with good Mavlink support.

5

@newcomer9747 I would like to add some Mangos to the mix. Like ELRS, MLRS is being actively developed, not that TBS isn’t or even RFD but there is a much larger active community in both ELRS and MLRS. It too can do rc and data works on hardware that also does ELRS so there is off the shelf stuff out there now available. Take a look at the docs and possibly join the discord if you have questions the docs can’t answer. Like others have mentioned each one is different even though they all are 900mhz systems. they do share some similarities.

6

Thanks! That’s alot of useful information that I need to digest. I’m selling off the TBS then, sad.
Now I’m down to two options; Dual band ELRS 4.0 Mavlink or Matek single band mLRS (900 or 2.4).

One of things I want to do is controlling the gimbal with two input devices. 1; rate control of the gimbal with a spacemouse set up in the joystick page in mission planner. 2; XF Head tracker using an audio cable connecting the head tracker to trainer port of a TX12 radio. Only one device can be used at a time. Can both be done with ELRS Mavlink and Matek mLRS? Would the result be a laggy one?

7

If you’re buying ELRS hardware specifically to run Mavlink I would go with dual chip LR1121 hardware. At this point the firmware is only working on one band at a time, but havinge the dual radio (Nomad, XR4) will give you the best performance.

8

More like fancy caviour :sweat_smile:. I wouldn’t use RFD unless somebody else is paying for the hardware or I absolutely needed encrypted communication.