Best antenna for mkr nb 1500

i'm having trouble sending data to the hologram cloud. my system only needs to send a data message when a sensor gets tripped(should happen infrequently) and i'm finding that it is failing to connect to the modem or TCP socket rather often. At times it seems the board ends up frozen.

maybe part of my issue could be solved by a better antenna. does anyone have any recommendations?

on a side note, is there any code or library that does a better job of attempting to establish connections than the mkrnb library? i see that zbelding has created some code that runs without it, but i'm not sure how i could port that over to something more simple like my program. my coding experience is pretty new.

i have updated the sara modem firmware already.

Any good quality LTE antenna designed for the frequency range being used should work fine. I have been using a omni-directional whip antenna like this one: https://www.multitech.com/models/95218161LF

I was using a directional antenna before the firmware upgrades to reduce modem lock-ups. After the updates I went back to omni-directional.

As far as arduino libraries, I'm afraid you may be up against it in terms of stability.

I spent many hours coming up with a sketch that talks directly to the modem and can recover from the numerous ways this ublox modem can get stuck(at least in low signal areas). I switched to a mega with a mikroe SARA R4 modem, but the communication with the modem is pretty much the same. This has been running for many months without issue.

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Thanks man this is helpful to know. I’ve read through your code a few times to try to understand it. I think it will require some more reading to see if I can somehow modify it to get called whenever a sensor trips and to speak with the hologram cloud rather than thingspeak. This mkr board has turned out to be quite a riddle in more than one way

so i haven't been able to find anywhere in stock with the modem you've got. what do you think of this one?: https://www.mouser.com/ProductDetail/Molex/213523-0001?qs=GBLSl2AkiruXZHLxZtK6TA%3D%3D

i'm not sure what frequency range i'm looking for. i know i'm in the united states, the product design should be usable anywhere in the country, and i'm using the hologram SIM card. i'm reading that the LTE-M bands range from 699-2155 and the NB-IoT bands range from 617-2200. Since that antenna ranges from 698-2690 i would have issues in the B71 NB-IoT band. would this be a problem and should i be looking for an antenna with a lower range? it's also got 2.3dBi, 4.8dBi gain and 2 bands. are those ideal?

I am no expert, but that looks like a good choice to me.

ok thanks!

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