How to activate cellular service with Mangoh Yellow?

Hi I’m using the mangoh yellow to test out the WP7702 cellular modem and I was told that you can make voicecalls with it as well as do SMS. I found the command needed to make a voice call, that is ATD##########; But when I try this command, it says I don’t have a carrier, which makes perfect sense since I never signed up for one. I was wondering if sierra wireless provides that service or if I should get a sim from another company? I noticed it has a sim slot but nothing happens when I insert an active sim card in there. Hope you can help. :slight_smile:

*Update:
So I figured out that the sim slot there is definitely needed to make a phone call or do anything with cellular but for some reason the network will not register. (at+cops?) returns 2 which means its deregistered from the network and (at+cgreg?) returns 1,4. I’m not sure if that’s bad but I think it’s supposed to be 0,1. I’m just wondering what I should do to get it to register to my network. I’m using t-mobile by the way. I read sometimes this just takes time. Could that be the problem?? :smiley: Let me know if you have the solution!

Here says voice call is not supported in wp77

Its not supported? It should be able to make calls though. If you look at the description for wp7702, https://www.sierrawireless.com/products-and-solutions/embedded-solutions/products/wp7702/. Doesn’t this cellular modem support calls? This is the modem that’s on the mangoh yellow. And its okay if it doesn’t have a speaker or something. It just needs to make a call to serve as an alert.

You can see here

And also here: