Hi
I recently purchased SparkFun Thing Plus - nRF9160. The firmware is from zephyr example code to connect to aws iot. The code works perfect for nrf91 dk board.
However, when using sparkfun board, we found that the connection to the internet is slow and sometimes not able to connect (but using dk board will connect instantly at the same geographical location in USA). AWS servers rejected the connection due to poor signals. I think it’s antenna issues so I try to find ones that satisfy the requirements as shown below.
Here is a list of antennas from digikey that we’ve tried (link incluced):
Ezurio
Taoglas
SZK
KYOCERA
KYOCERA2
SRFL
However, none of them work. I’m using the SIM card and service from AT&T LTE-M network.
Does any of you have any pointers on which antenna to use or if this board from sparkfun has limitation while the regular dk board from Nordics doesn’t.
Hi,
Thanks for answering the question. My apology that I post the wrong link for nrf91 DK. It should be nrf9160
On a separate note though. Even the connection is poor, it may once a while connects to it. However, it always return iot: aws_iot_connect, error: -119
I look a little into the code and it means connection already in progress. If I let ir runs longer. It will spit out -116 which is Connection timed out. That’s why I thought might be antenna, but I could be looking into the wrong direction since you mentioned that Kyocera is the same antenna they used on DK board.
Just to make sure: you are testing one at a time, with a decent time gap between? Or with different SIMs? I wonder if there is some AWS setting you can change/alter (increase timeout, ensure multiple concurrent enabled, etc)
Otherwise I’d say keep researching the error (enable verbose output if you can)
I tested them at separate time. I wrote the code and make sure everything works on nrf9160 DK before I flash the same code and swap that same SIM card onto the sparkfun nrf9160 board. I don’t think I have control of the timing and anything regarding connecting to aws. I’ve esp32 that connect through wifi and they works with the same aws policy and CA-cert, so I think it’s valid to have same cert and policy on different nrf91 board (though I never turn on them at the same time since I only have 1 SIM card)
One thing I don’t quite understand is the electronics part for the antenna, maybe you can help me out if you know anything about this. I found that DK and sparkfun has different capacitor and transistor values, not sure if this will impact the antenna.
Here is a snapshot I got for nrf9160 dk
Eh, I don’t know much but I’ll take a swing - I would presume it does, but the values needed are usually based on the trace length & pour type…you could use EAGLE to view the traces https://cdn.sparkfun.com/assets/0/0/9/c/6/nRF9160ThingPlus-EagleFiles.zip and then use an online calculator & compare with the DK version, if so inclined, and see if anything seems funky
