Prototype with nRF9160 does not register on network, returns +CEREG: 0

RE: Prototype with nRF9160 does not register on network, returns +CEREG: 0

ketiljo — Wed, 17 Mar 2021 12:33:30 GMT

Great to hear that you found the cause.

cheers,

Ketil

RE: Prototype with nRF9160 does not register on network, returns +CEREG: 0

EmbeddedDan — Wed, 17 Mar 2021 11:06:06 GMT

Hi Ketil

We have found the problem with the prototype. We increased the voltage to the module to 3.6V and now it registers with the tower and we receive an IP address.

Thank you for your assistance, we are using the 4.7uF as you suggested.

RE: Prototype with nRF9160 does not register on network, returns +CEREG: 0

EmbeddedDan — Wed, 17 Mar 2021 06:25:57 GMT

Hi Ketil

I did not have any success with a 4.7uF capacitor. Do you belief the issue we are experiencing to be an RF problem?

Signal strength on the nRF9160_DK is: +CESQ: 99,99,255,255,23,57 and on the prototype its: +CESQ: 99,99,255,255,255,255

The local network using band 8 (900Mhz), this is the output with constant carrier at 900MHz (AT%XRFTEST=1,1,8,9000,17,0,4,12,0,0,0,0)

Output with QPSK modulation (AT%XRFTEST=1,1,8,9000,17,0,0,12,0,0,0,0)

Output with BPSK modulation (AT%XRFTEST=1,1,8,9000,17,0,3,12,0,0,0,0)

RE: Prototype with nRF9160 does not register on network, returns +CEREG: 0

EmbeddedDan — Tue, 16 Mar 2021 13:17:15 GMT

Thank you for looking at this Ketil.

Yes the antenna is an external antenna. At the moment L4 and C24 are not placed and are shorted with a blob of solder. L5, C25, C26 and C27 are not placed and are open circuit. We will remove these matching components in the final PCB.

I'm going to change C29 to 4.7uF and give it a try.

RE: Prototype with nRF9160 does not register on network, returns +CEREG: 0

ketiljo — Tue, 16 Mar 2021 13:06:53 GMT

Hi Danie

The layout doesn't show the LTE antenna. Is this an external antenna with a U.FL connector? If so, the components L4, C24 and L5 are not needed as the antenna tuning will take place on the antenna itself. What happens if you plug the antenna into J1 and remove L4?

Note if you are using GEN2 modules, C29 must be 4.7 µF, it will not work with 47 µF.

cheers,

Ketil

RE: Prototype with nRF9160 does not register on network, returns +CEREG: 0

EmbeddedDan — Tue, 16 Mar 2021 12:43:51 GMT

devzone.nordicsemi.com/.../0827.Schematic.PDF devzone.nordicsemi.com/.../PCB0A00070_5F00_Gerber-and-NC-Drill-files.zip devzone.nordicsemi.com/.../PCB0A00070-433MHz-Radio_5F00_NO-IoT-variant-PCB-3D-Drawings.PDF

RE: Prototype with nRF9160 does not register on network, returns +CEREG: 0

ketiljo — Tue, 16 Mar 2021 12:22:13 GMT

Hi Danie

Can you share the schematic and gerber files for the board you've made?

best regards,

Ketil Aas-Johansen