WISMO228 with T-Mobile Network in US

Hi guys,

Does anyone having problem registering to T-Mobile network using WISMO228?

Using the AT+CREG? command yields 1, 0.

Is the SIM enabled/active?

Do you actually have any T-Mobile signal?

What does at+cops=? tell you?

Hi,

Running the AT+COPS? command yields:

+COPS: 0,0,“T - Mobile”

But that only shows after forcing the frequency band into 900MHz and PCS1900 using:

AT+PSRDBS=1,18

But, after a while, it will get deregister again from the T-Mobile network.

The AT+CSQ value is not very good. Around 7-9. But, I believe even with that it should get registered.

Any clue what could go wrong?

Surely the USA uses 850MHz :question:

en.wikipedia.org/wiki/GSM_freque … d_GSM-1900

But, T-Mobile is using the 1900 MHz band, so that won’t really affect?