Few months later iv'e purchased 6 more of them and all shields has the same behavior - they shuts down on network registration.
First of all i thought this is power issue, so i bought LM1085IT-5.0 module, and made power supply (connected it with 10 uf tantulum and simple cap) - same thing.
Then i connected modem directly to 18650 lipo cell battery - same behavior.
I even updated firmware of a modem - result is that modem shuts down faster.
Guys i need help, i have 6 modems in shelf worth 70 eur total that i cant use
Are you sure the shut down is because of the power supply? Have you monitored the voltage and seen it drop when the module registers?
It sounds to be more like a configuration or communication issue than power related.
Well not really. I do not have such advanced equipment, and voltmeter might not be that quick to react to such drop. Nevertheless i do now believe the same - this sounds not like power issue - connecting module directly to battery should have eliminated this.
Due to configuration - i have no clue (neither does google apparently) - if someone could suggest something i would be super grateful.
Since i do not have any other meant to monitor voltage drop as with voltmeter, i cant be 100% sure, maybe drop is very fast, although connection to battery should have eliminated this.
And if somebody has any, ANY ideas on configuration - please share those with me because i'm totally out of ideas