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15

The IATA Lithium Battery Guidance Document is as close as you can get to a worldwide set of guidelines for battery transport by plane. The section which I assume applies to your device is 2.3.5.9, which states: (a) each installed or spare battery must not exceed: for lithium metal or lithium alloy batteries, a lithium content of not more than 2 g;...


7

Most cellular providers use Private IP (RFC-1918) ranges (e.g. 10.0.0.0/8) and NAT for their networks which means it is not possible to directly access a device connected via these networks remotely as it is behind a proxy server. Even if they are using fully routed networks the IP addresses are handed out dynamically and can change at any time. Having said ...


6

Parameters to an HTTP GET request are key/value pairs, separated by an ampersand & The key and value are separated by an equals sign. Your use of DeviceData=T=<value> breaks this rule. See this page, which explains that you need to use %3D for the = which is part of the value. I.e. DeviceData=T%3D<value> But, ask yourself if you really ...


6

Have you looked at Particle.io or T-Mobile? T-Mobile offer unlimited connectivity for $25/year per SIM. They also have a web management platform, API and can optionally integrate with Twilio's platform. T-Mobile also commits to running 2G services until at least 2020: T‑Mobile supports IoT customers using 2G networks, giving them a clear roadmap from 2G ...


6

This confusing behaviour is typical. The underlying reason is that it is up to the carrier to decide what to do with the APN setting — unlike most configurations of this form, you're not actually configuring any connection setting. Instead, you're just passing to the carrier a text string. The carrier may do a number of things with the APN you've specified: ...


6

As Bence says, it depends on the chip, and accuracy needed. But I'd like to add one thing: many GPSes output speed and heading (direction) in one of their NMEA sentences. If your GPS chip does this, you may use this directly, and won't have to calculate anything—simply use the values provided by the GPS.


5

It strongly depends on the MCU you have, but I think any microcontroller on the market could handle this task easily. Calculating velocity and direction from the coordinates is not a big deal. I think parsing the GPS sentences takes more CPU time. So if you are just tunneling the GPS data through the GPRS link, unprocessed, so the whole NMEA sentence in one ...


5

If the device is powered, and the radio is capable of being powered, then this is likely to be prohibited by the carrier. You should find the specific carrier will provide regulations for what can legally be shipped on a specific route. The final consideration is that encryption technology is also restricted for international shipping.


4

As a person that created fleet management system processing data from devices with GPS receivers that currently serving two million units that consists from more then thousand of different types of such trackers from hundreds of manufacturers worldwide I have only one advice to you - do everything you can on the device side and rely on the server only for ...


4

The problem was bad contacting between SIM card contact block and the board. The problem was difficult to find because when I touched the terminal for measurement it makes pressure to the board, the contact happens and the problem couldn't be observed. I made a check list for resolution: Is SIM card working? Are voltages on card correct? Can bus signals be ...


4

You can enable extended error reporting, by sending AT+CERR. Different devices will give different informaiton, but you should at least get some diagnostic help/hint. For instance, this page says AT+CEER - Extended error report Execution command causes the TA to return one or more lines of information text , determined by the ME manufacturer, ...


4

As a GSM capable device you must switch it to Airplane mode. Which means the device RF interface must be completely shut down. Basically what you have described can be any smart phone, and I believe those can be delivered by air post as long as they are in airplane mode. But certainly if they are powered off.


4

AT command set for GPRS network is standardized so you can search for help on other pages like this [link1] and this [link2] In addition to that, be advised to check examples from this link too [link3]. Example bellow is just a fragment copied/edited from this page, so I believe that can be good starting point. Be advised not to use specific commands ...


3

I've found this library useful to solve issues with authentication. If you encountered same issues on GSM modules with Arduino, it may help you as well: https://github.com/elementzonline/SIM800_MQTT


3

As per SIM800 AT command Manual, you can set HTTPParamTag to USERDATA and send content in HTTPParamValue. You can pack all key-value pairs into HTTPParamValue and parse to retrieve individual key-value pairs.


2

You probably already know more about this, than even 3GPP does. Looking at their documentation, which is not to be read by the faint-harted, it seem that NB-IoT is using a new special category of the LTE Advanced Pro, in 3GPP Release 13. Again, note that release 13, does not mean LTE UE Cat 13, but the new category NB1. For further info, look here and here, ...


2

There is a good library called GSM_MQTT.hfor sending data through mqtt from GSM modules. You can refer this site. Hope this helped.


2

Orange pi has some boards that might be what you're looking for. Look for their "IoT" models; some have 2g, 3g or 4g modules built in.


2

An SMS message has a maximum size of 160 chars. While modern devices will allow you to send what look like longer messages they are just multiple messages that the devices concatenate together when received.


1

All right. Thanks to those of you who posted comments. It turned out to be an issue with the baud rate! Its always the simple stuff. Adafruit said this thing has auto baud meaning you can use any baud rate but they are wrong. It requires 115200 to work properly. Also I'd like to point out that there was nothing wrong with my setup. Sometimes you should trust ...


1

A GSM phone or modem receives messages automatically. Basically you are just retrieving the messages from the memory of the device or SIM card. To select the message storage used to read the messages from, you have to use the "AT+CPMS" command. For example, to read messages from the SIM card use: AT+CPMS="SM" More details you can find on this ...


1

We use Sierra Wireless - one reason we picked them is for their detailed Web Service API documentation. Their model is that individual devices connect to them; sensor readings etc are retained in their "data lake"; and we use the web service API to poll (or be triggered) to discover uploaded data. It's working for us for the moment.


1

To get ampersand to work properly, it also needs to be url encoded. Try substituting it with %26 and you can have it in the url. Dot from float should be %2E to work properly. Values can be checked from https://www.w3schools.com/tags/ref_urlencode.asp


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