We are designing a low-speed cellular data-only modem for use in the USA (<1mbps) and we have been trying to get a SIM to use during our development, with our cellular provider AT&T Cellular.
When we sent the IMEI data from the ublox module on the LTEStick (LARA-R6401D-00B) they responded that it is not compatible with ATT in the USA, and supposedly the frequencies aren’t supported.
The UBLOX and SparkFun web pages both show this device as 100% ATT frequency and protocol compatible. But ATT says it’s not.
Who is wrong about this?
David Smith
I’d presume AT&T is in the wrong…unless there’s some caveat about it being compatible with AT&T but not in the US? (that seemed unlikely to me, until I found this https://portal.u-blox.com/s/question/0D … and-larar2)
If that post doesn’t have enough guidance you could try posting a similar topic on the u-blox forums
ATT was pointed to their own documentation on-line that the uBlox products are compatible, but now they’ve switched to saying that the ‘end-device’ must also be approved and certified for use on the network… I get the idea of being careful with network access, but how does a group or person ever get ability to test their product or project with a LTE Stick if they cannot get a SIM to test with? I can plug in most any SIM I bet and operate it, but I want to be up-front with ATT about the project and get the SIM that makes the most sense and follow the spirit of their rules.
How do other LTEStick users do this? Certainly some users are just fly-by-night and use a SIM from some other device, and count on the module and its FW to be approved, but they could certainly generate failure codes on the network if they wanted to… It seems like ATT and other cellular suppliers should be able to generate a development-oriented SIM associated with a particular project (maybe more expensive?) that allows a IoT or other project development to continue forward while they validate all their code and (if needed) get a certification for their own developed end-device equipment. What do those customers do?
Yeah, the SIM card variable can be problematic…
We have tested a fair amount of different SIM cards(we cannot test all SIM cards/plans/carriers/countries). Some work well, some don’t. I would suggest that you keep trying cards from different carriers and plans until you land on one that works.
Sorry this reply was not more informative there. Let us know if we can do anything else.
Update: ATT gets uppity about putting unknown stuff on their network, but we had good luck just asking for a SIM for a known approved device (i used a pepwave modem IMEI) and the resulting SIM card seems to be working fine. Thanks for your help.