Cannot connect over 4G using the ZTE MF833U1

[Jowelboy]

I have a spare ZTE MF833U1 so tried it with a Three sim however I could not get it to connect over 4G.

I changed the settings from '4G only' to '3G only' and it connected slowly as 'HSPA+' so I manually selected the network and there was a 'Three 4G' connection that it said was available, but it would not connect.

The software detected that I'm on the Three network but just couldn't connect.

I tried changing the APN from the automatic setting to 3internet and also three.co.uk but nothing changed, I could not connect to 4G.

All of the above was done with the ZTE MF833U1 dongle plugged directly into my Windows PC.

I *also* had the same issues when I plugged the dongle into my TP-Link portable 4G router - TL-WR902AC.

To confirm, when I put the sim into an actual phone I got 4G no problem and it was nice and fast, so I know I have a decent 4G signal where I am.

Any thoughts would be greatly appreciated.
Thanks in advance for any help.

[JonathanB]

Hi Jowelboy,

Thanks for joining the Three Community. 

I'm sorry to hear that this dongle isn't working on 4G properly. I'm not familiar with that model, did you originally purchase it on a Three contract or PAYG? Do you remember when this was?

Based on the tests you've tried so far, it does sound like this would be a fault with the device itself. Assuming it hasn't been supplied on a contract that's still in its minimum term with us, I'd recommend getting in touch with ZTE directly.

Hope this helps,
JonathanB

[Jowelboy]

Hey Jonathan, thanks for getting in touch.  No, it wasn't bought from Three but following on from my original post I tried it with an o2 sim and it worked swimmingly well loads of 4G etc.  So it's made it more frustrating that I can't get 4G with Three.  I can confirm I have a good mobile signal with Three and my feeling is that maybe the APN settings are not correct or something similar that means it's being rejected when attempting to register with the network.  On the device is a helpful LED.  It's red when it's not connected and blue when it does.
Under Three with 3G is goes blue, under o2 with 4G it goes blue but under Three with 4G it stays red.

To confirm, with the Three sim in a phone I get full bars and 4G+

[JonathanB]

Thanks for the update @Jowelboy,

Okay very unlikely to be a device fault in that case, or the SIM card itself.

It could be that there's differences in what specific 4G bands the phone and dongle can connect to, hence the differing signal, this could also mean there's a fault that's only affecting certain bands. Are there any signs of faults or engineering work on our Network Status Checker for that area?

On the APN side of things 3internet is definitely the correct one for mobile broadband devices.

JonathanB

[Jowelboy]

Hi again Jonathan, thank you for persisting with me, it's greatly appreciated!

Unfortunately the Status checker is giving an error when I enter a postcode so I can't help right now with that.  It's interesting about the different 4G bands..  What bands do Three *generally* use?  I know Im within an area that has 5G so it's modern enough.  Does that help?

The spec of the ZTE MF833U1 says this which I hope is useful:
Supported Frequency Bands:
- FDD-LTE Bands: 1, 3, 5, 7, 8, 20, 28
- TDD-LTE Bands: 38, 39, 40, 41
- DC-HSPA+/HSPA/UMTS Band: 1,2, 5, 8
- EDGE/GPRS/GSM Quad Bands

[JonathanB]

The main bands should be 1, 3, and 20, so you ought to be covered, assuming there's no faults. I'll send you a PM so that we can get this looked into in more detail.

JonathanB