M2 5G development board

I’m considering purchasing the 5g development board. I plan to use this with a Visible wireless SIM card to have always on wireless internet in my motorhome. Looking for feedback on how this hardware plays on the Visible/verizon network.

I don’t see that many reviews or topics on this hardware so I’m a little reluctant to dive in at the moment since I have a solution that works ok for now.

Another question……Is there any vendor that sells this development board with USA stock?

I’ve got a GL-M2 board in my travel trailer; I use it with my Slate AX (GL-AXT1800). I’ve been quite happy with the GL-M2’s performance and reliability. But, I do use the Slate AX/GL-M2 combo as a backup gateway and my primary modem/cell connection is Spitz AX (GL-X3000). Long story short: I bought the Slate AX, four months later the Spitz AX was introduced and I decided to buy it, a few months afterwards I had fallen in love with the Spitz AX’s cell connectivity and decided to buy a M2 board for my Slate AX as a backup.

I’ve never used the M2 with Visible - I have used it with AT&T, KPN (and 80+ country IoT SIM out of the Netherlands), Rogers and Telus (I’m Canadian, eh?). The M2 is fairly flexible and you can adjust the TTL and MTU, and its very easy to change the IMEI to match a device that a given carrier might expect to see on its network. As the Spitz AX and the GL-M2 both use the Quectel RM520N-GL modem, posts on these forums about carrier issues with the Spitz AX will usually apply to the GL-M2 as well. In the past, there have been some issues reported (and fixed) about Verizon/Visible, so make sure to look around.

I’ve seen various GL.iNet devices for sale on Amazon, but never the M2 board. I ordered mine directly from GL.iNet’s online store - it was shipped via FedEx from Shenzen, China to Toronto, Canada in five days (technically, I ordered it on a Friday evening, it was shipped on Monday and received that Friday).

There is no official enclosure available for the GL-M2. I 3D-printed one I found here on the GL.iNet forums - and I’ve been quite happy with it: GL-M2 5G Development Board enclosure? - #9 by sharkfi

As a reminder, if you’re looking for a plug-n-play solution (i.e. connecting it to a router and the GUI automatically supports it), the GL-M2 is supported by the following GL.iNet devices: Slate AX (GL-AXT1800), Beryl AX (GL-MT3000), Brume 2 (GL-MT2500), Flint (GL-AX1800), Flint 2 (GL-MT6000)

On the Slate AX, the modem configuration in the current (stable) firmware falls somewhat behind the Spitz AX. The Spitz AX’s GUI supports display of connected bands, band locking, and tower locking - the Slate AX does not (although all these functions can be accomplished with manual AT commands).

Power-wise, the GL-M2 uses a 5.5x2.1mm barrel plug and accepts 5.5-17 volts, so it can be directly wired to an RV’s 12V system: GL-M2 Dev Board power voltage - #2 by Dipin

And, just to geek out a little bit… one future possibility I’ve been considering is to build a waterproof housing for the GL-M2, attaching it to the back of a directional panel antenna (minimizing cable loss similar to InstyConnect’s approach), and raising it on a pole with long 12V cable and USB cable to connect to the Slate AX inside.


I had the same experience as RVer, the board ships from China, BUT it is super quick shipping. I got it in 5 days.

Hey sharkfi, thanks for creating and sharing that case - I really do like it. You inspired me… after I had your case printed at my local library, I decided to buy a 3D Printer and try some designing and printing myself; I’m hooked!

Thanks for the deatiled feedback. I was thinking the same thing about locating the M2 very close to an external antenna to minimize cable attenuation. Like you said just run 12V and USB to the device and good to go. I think USB 3.0 can support something like 50 feet of cable length.

I think I will go ahead and give the M2 board a try. I did hunt around on the forums regarding the RM520N-GL and how it interacts with Visible/Verizon….read a bunch of posts….pretty confident I can get it to work. I could ultimately switch to another carrier but I like the unlimited data for TV and other streaming services. I have AT&T as my cell phone carrier which gives me flexibility if I have a marginal signal on the Verizon network. I tether my carry around cell phone in that case.

I just got my Slate AX (GL-ATX1800) up and running yesterday. I had been using a Slate 750-EXT for a couple of years….what an improvement the Slate AX is.

Put an order in for the M2 5G board. While I wait for it’s arrival, I do have another question. I realize there are 4 antenna ports on the device and that each makes a separate connection to the cell tower for purposes of MIMO. Would I have an issue if I were to put a single hi gain yagi antenna on one of the ports while keeping the other three antennas in place? My though was that if I have a marginal signal that I might get a better connection on one of the channels. I realize they make 4 gang yagi antennas to solve the problem for all 4 channels.

Does my logic have any merit? Would appreciate any feedback on this idea.

It certainly won’t hurt, but it may not help. The key thing to remember is to always have antennas connected to all ports at all times while its powered on; but yes, you can mix-n-match with varying levels of success.

Over the past summer, I’ve experimented with my Spitz AX (sorry, handn’t bought my GL-M2 until fall - but, its the same modem and I expect it to perform similarly) in various remote locations my trailer. I have a 2x2 MIMO omni-directional antenna on a 20’ flagpole. For the most part, in low-signal areas, the stock antennas had far better throughput (note: I have a fibreglass trailer). But, in one very remote area where even my phone was constantly connecting/disconnecting and couldn’t maintain a cell signal, the pole-mount antenna did come through; I went from nothing usable to a stable connection with ~15/5 Mbps connection.

One observation: after tuning it on and booting up, it takes about 2 more minutes for the modem to adjust to the antenna and stabilize the connection. I have no idea if this will impact aiming a directional antenna - I really hope not.

For a single antenna, connect it to the ANT0 SMA connector. The connectors are labeled 0-3 on the modem - as part of the setup, YOU have to connect the modem’s antenna pins to the GL-M2 board’s SMA connectors using the provided wires (they easily clip on; technically, you can do it in any order you’d like.

Here’s a link to the Quectel RM520N-GL Hardware Design manual (the antenna info is on page 53: QUECTEL RM520N-GL Hardware Design User Guide

FWIW, for my trailer, I’m looking at a Waveform 4x4 panel (directional) antenna. The gain is a bit less than a yagi setup, but its easier/lighter/smaller to pack away, plus it has a bit wider field-of-view for both aiming and bringing in signal reflections from the tower caused by trees/hills/etc.

I get your point about having to store and deploy a yagi / log periodic antenna in an RV when on the road. Especially when I’m moving around and only stopped for one night at a time. I have had success with Patch / Panel antennas in the past on 2.4 GHz wifi. It was a decent antenna—12" pig tail–with a claim of 8 dbi gain. Wasn’t able to measure the gain but I did get good results WRT throughput performance in comparison to what was a marginal signal using an omni antenna.

Anyway…I did see the Waveform 4x4 and that might be a good option or me as well. I will keep hunting around until I can start experimenting with my M2 board. Should have it in a few days. Thanks for the link to the design guide on the RM520N-GL.

I’m looking to get more data from my modem while using the 5G development board and the Slate AX 1800. Is there an interface I can run that will give me cellular specifics i.e. cellular band, channel bandwidth, signal strength etc. Any guidance on this would be appreciated.

I did find some posts on the open WRT forum that detail some code to get the date out of the modem. Just wondering if anyone over here had any success.

I’ve been experimenting with the latest release candidate (RC) firmware for the AXT1800 - it does include the information you’re looking for:

HOWEVER, despite being RC, the firmware has got a few frustrating bugs (and I’m running it clean with no additional packages or configs) - I don’t advise it for production.

On the other hand, if you’d like a somewhat clunky solution with the stable firmware, you can issue a couple of AT commands:

  • For the current network operator: AT+COPS?

  • For the connected bands etc (freq,bandwidth,band,scell_

Here’s the RM520N-GL’s AT Commands Manual

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Thanks again RVer. I tried the new firmware and I like the added stats page. Unfortunately I got a painfully slow connection speeds with my M2 5G modem and the 4.5 firmware. Not sure why but will need to play with it some more. Question??? Where do I issue the AT commands? Do I do it on the SSH terminal screen?


Any time, magnetom. We’ve got similar use cases and its interesting to compare notes with you.

painfully slow connection speeds

Thanks for mentioning this… I’ve been having the same problem with 4.5 and was going nuts trying to figure out what I had done wrong. Looks like its just the firmware and I should probably just go back to stable.

You can enter AT commands under the three-button menu on the Cellular Connection block. Here’s the location in the 4.5.0 RC firmware (it has a similar-ish location with the earlier firmware). I did have to change the port to /dev/ttyUSB2 - I think yours should be the same, but worst case, just try them all and issue an AT+COPS? until you get a response :

Ahhh…Perfect. I found that page but didn’t realize that I had to send the commands to USB2. Go figure…
Anyway, I’m going to give the 4.5 firmware another try tomorrow morning and attempt to figure out why it is so slow. I abandoned it this morning after I saw the speeds. For reference I went from 50 Mbps to around 3 Mbps. Tried a few different TTL’s but no help.

I experimented with latest release candidate (RC) firmware for the Slate AX1800 (version 4.5.0) again this morning. My main focus was to get the system past the Visible/Verizon hotspot throttle of 5 Mbps. On the 4.4.6 firmware I need to set a TTL of 88 to get past the throttle.

Here are my original 4.4.6 results…

Again, with the 4.5.0 firmware both upload and download are throttled to 5Mbps. It doesn’t appear that any manual changes to the modem settings have any affect. i.e. if I change the TTL to 88 in this page…

These are the custom rules I have been using in the firewall…

iptables -t mangle -I POSTROUTING 1 -j TTL --ttl-set 88
iptables -t mangle -I PREROUTING 1 -j TTL --ttl-set 88
ip6tables -t mangle -I POSTROUTING 1 -j HL --hl-set 88
ip6tables -t mangle -I PREROUTING 1 -j HL --hl-set 88

None of these conventional solutions seem to have any affect. I remain stuck on 5 Mbps throttle in the 4.5.0 release candidate.
Next step will be to drill into the log files and try to see what is going on. If anyone has any ideas I certainly would like to hear.

Would you guys happen to know what the max speed for GL-M2 is? I am comparing mobile network speeds between M2 and GL-AX3000-5G and it seems the GL-AX3000 is faster. I have seen my AX3000 achieve >300 Mbps where I am located, but have not seen my M2 achieve >300 Mbps.

Tops I’ve seen on my M2 (at my location) is around 250 Mbps.

I just want to pop in and say thank you for the screen shots. I also received my M2 5G dev board and finally realized it was ttyUSB2 I needed to connect to. The problem I’m having, maybe someone can point me in the right direction, is that regardless if I put in a 5G Tmobile Sim or a programmable Sim card, the at+cops=? hangs and ends with a CME ERROR:3. I’ve found that maybe means the modem is hanging, also tried a suggested AT+COPS=2 followed by the previous command.

Would any of you with a M2 5G Dev board be able to run that at+cops=? command with the latest cutecom with RTS/DTR checked and CR/LF selected? I suppose doing it from the GL INET GUI would be the equivalent.

I should’ve mentioned the same Tmobile 5G sim in a phone is able to see/connect to the towers around me. I’m probably doing something wrong or missing something with the development board as I’ve yet to see it find any towers/connect to anything while plugged into a Linux desktop (I don’t have the GL INET router yet).

I ran at+cops=? on my M2 5G development board and the command didn’t return anything. I did not get any error messages either.

Here you go…

That’s the reason: