Questions tagged [gsm]
GSM stands for Groupe Spécial Mobile. It is a standard set developed by the European Telecommunications Standards Institute (ETSI) to describe protocols for second generation (2G) digital cellular networks used by mobile phones.
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RF power transmission control in U-blox GSM modules
I am using the SARA-U270 GSM module and want to test energy-saving techniques. One technique I would like to try is power transmission control, adjusting the transmission power in dBm based on the ...
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Which signals (Wi-Fi, mobile phone, and GPS) can reliably be blocked by aluminum foil?
There seems to be conflicting information regarding which signals can be effectively blocked by wrapping the device in aluminum foil.
With effectively blocked I mean block the signal as such that the ...
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GSM and LTE-M connection with SIM7070G for MQTT data transmission
I am working on a tracker project using the SIM7070G modem from SIMCOM. The objective is to maximize the connection by working with both LTE-M and GSM, aiming to send location data via MQTT.
I have ...
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Sim800L can't send SMS
I know it is somehow weird problem, but I don't know what to do.
I am using SIM800L GSM module with ESP8266 nodemsu v3 and they are connected via UART serial communication.
I am using this code to ...
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Why Phase1 GSM is mentioned to be a 3GPP release?
In some references such as Wikipedia (although wiki is not a reliable reference), GSM phase 1 is mentioned one of 3GPP releases while 3GPP itself is founded in 1998/1999 while GSM Phase 1 is ...
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SIM800L GSM module humming noise
I am trying to play audio over the call by using SIM800l
I am using this "DFPlayer mp3 module" to play audio and connected its AUDIO OUT to the MIC IN of "SIM800L GSM module" and I ...
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Can't get DTMF tones from sim800L gsm module
I am using esp8266 and sim800L gsm module to recieve incoming call and get the DTMF tones from the caller and take an action according to the received number, i am searching for about 3 days and found ...
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SIM800C not working as expected
I've created a custom board with a SIM800C. I'll show the schematic above:
My VIN is aproximately 4.8V. MY "4V" line is constant. I'm able to comunicate with the module, but sometime's ...
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Powering 4V, 2A GSM/GPRS module
I am currently working on a project that involves powering a Quectel GPRS/GSM module, which requires a current of 2A at a voltage of 4V. I intend to power the module using a 5V adapter and a lithium ...
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Sending/receiving a continuous stream of data using SIM7600
I have a SIM7600EI connected to an STM32 controller over UART. I am able to send HTTP POST requests for small chunks of data using AT commands. Currently, I want to send a continuous stream of data ...
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Different GPS antennas not working properly on my GPS module
I have a SIM808 based board. It is working fine with an antenna similar to this: enter image description here
Now I want a smaller one; I bought 3 from Amazon for testing. The same voltage, frequency ...
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SIM800L external supply issue
I have built an Arduino project that sends data from sensors to a specific website using the SIM800L GSM module. My problem is when I power whole circuit it from a computer or a charger, it works fine....
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How did old mobile phones amplify signals lower than the noise floor?
In the early days of GSM in around 2000 when the network was still not fully deployed, it was common for me to receive very low signal, even sometimes No Signal due to out of network.
I used to use a ...
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Identify this component: BEF1592 2143
This component is placed in the signal path next to a multi-band GSM antenna. It seems to have 3 terminals - 1x GND and 2x in signal path. I suspect it is some sort of bandpass filter, but can't ...
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I hear noise after turning SIM7600 on
I have a question about the GSM 7600g-h module which I am currently using to send data by TCP (Transmission Control Protocol) .
The problem with using that kind of GSM I bought is the noise after ...
