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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Battery powered GSM for MQTT [closed]
I working on device which take pin on off status and send it to server.To send it to server, we have used sim7000e GSM module, on which we run MQTT.GSM module consumes power arround 40mA average. It ...
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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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Using TINYGSM Client write function for PubSub's client.publish()
I have an application of data logger done on ESP32 where a JSON string is published to the MQTT server(QOS 0) using PubSub Library via TINYGSM. I am attaching a sample of the packet sent to the MQTT ...
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SSL AT command issue after switching from SIM7600EI to SIM7600 CE,
I had a simple application which POSTs a JSON payload to an API endpoint, running on an STM32 controller with SIM7600EI as the modem.
Shortage of SIM7600EI in the market forced me to switch to 7600CE ...
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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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Connect Fona3G SIM5320 to cloud over MQTT protocol using GPRS/TCP with stm32
I am seeking assistance in connecting the FONA 3G SIM5320 module to the cloud via TCP connect to establish an MQTT connection. I have successfully connected the module using GPRS connectivity by ...
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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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SIM7600 module. Transparent mode issue
I use a SIM7600G communication module.
I'm trying to send data in transparent mode via TCP/IP. But after I establish a connection with the TCP/IP server, I get an "error" in response to the <...
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How to "soft" reset SIM7600X after swapping SIM cards to make the modem find a connection?
I know that swapping SIM cards when the module is turned ON is a bad idea, but in doing so I'm trying to simulate another practical scenario. I come from an Asian country where prepaid SIM cards are ...
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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 ...
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SD Card Write Problem
In my project I download a ".hex" file from FTP via GSM connection and write it to a SD card. But I have a problem: I download file and all loops work well but when I access the file on ...
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GSM Operator Register problem (CREG:3 Error)
I am using Turkcell operator (2G) in my application (28601). GSM Modem: Telit / GE910QUAD. I use the AT sequence listed below:
...
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How to connect GSM module and Arduino to the same battery?
I am using SIM800L which requires voltage range between 3.4-4.7 V with 2 Amperes. On the other hand Arduino Uno requires 7-12 V. The question is how to power both of them with the same Lithium battery?...
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Why does the SIM800C stop sending data to the server after three days of continuous use?
I created a device that monitors air quality. The measured data is then sent to a web server using an ESP32 (programmed in C++ with Arduino framework) and SIM800C module, which stores them in an ...
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Interface PCM module SIM800 , SIM808
I am planning to use a SIM800 or SIM808 GSM/GPRS module's PCM interface. I configured the circuit according to the datasheet. I send the 256 kHz clock from the micro to the PCM_CLK pin of the module ...
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EV1HMC245AQS16 bidirectional capability
I want to use EV1HMC245AQS16 as a RF multiplexer. I have a IoT device that I need to test with 3 different antennae. The IoT module will be connected to 3 different antennae via the RF multiplexer. I ...
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EV1HMC245AQS16 RF bidirectional capability
I want to use EV1HMC245AQS16 as a RF multiplexer. I have a IoT device that I need to test with 3 different antennae. The IoT module will be connected to 3 different antennae via the RF multiplexer. I ...
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Bad GSM network automated testing
We are using a 2G modem controlled by an MCU in our device and we want to do an automated test routine that tests our firmware for bad mobile network scenario. How can we create a system where a ...
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C8051F020 serial communication with GSM module (SIM900)
I am currently trying to interface the GSM900 module with a C8051F020 microcontroller using serial communication in order to send AT commands to the GSM from the 8051.
The TX of the microcontroller is ...
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How to correctly model a receiving antenna?
I want to amplify the signal received by an antenna for GSM signals. I am currently modeling the antenna as a 900 MHz sinewave generator and a 50 Ω resistance in series with it. However, I doubt this ...
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Difference of Milenage Version 1 and Version 2
I've heard in the telecom industry about Milenage Version 1 algorithm and Milenage Version 2 algorithm.
I want to know what are their differences?
The version 1 and version 2 have the same length for ...
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Can I determine antenna band without very expensive equipment and knowing antenna length?
I have a lot of GSM and WiFi antennas of various lengths and shapes with SMA connector.
I know of the antenna length relation with wavelength, but in some cases it is difficult or impossible to ...
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A6 SIM module keeps resetting
I'm using a SIM A6 module (Goouuu Tech A6, I believe it's the same) to send messages. The problem is, once I plug in a SIM card, it keeps resetting (the green led blinks and kind of interrupts after 3-...
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GSM module SIM800C 4V power supply efficiency of circuit
This is a follow-up question to https://electronics.stackexchange.com/a/436720/208059
I (SE not EE) am designing a circuit for a battery-operated IoT node. Power consumption is critical so the GSM ...
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Gsm switch to turn individual lights on
looking for some more help. I now have my led consumption sussed but have run into another obstacle which I require some help with.
I have 8 x individual lights which I have decided can be turned on ...
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SIM800L power switching with transistor
I use a TIP32C transistor to switch the power line of a SIM800L module, but unfortunately this method isn't working. The module is powered on, but it only blinks once every second instead of every 3s. ...
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Impedence matching required for very short PCB trace?
I have a custom PCB using 50 ohm impedance antennas for GPS (1.575 GHz), GSM (2.4 GHz), and LoRa (868 MHz). Currently using an impedance matched board with matching track widths of 6 mil. One track ...
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Anyone having a GSM module please confirm. Is it normal to have the terminals of SIM800L EVB antenna shorted?
My SIM800L-EVB GSM module wasn't registering to network even after providing good power supplies. On troubleshooting I found that the terminals A and B, to which the antenna attaches(see img attached) ...
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180m to proper 4G reception: which approach to take to ensure good bandwidth?
I have a cabin in a remote location in Norway, and as luck has it, no cell phone reception. There is great reception up on a hill nearby. I could erect an antenna there, and the cable would be about ...
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SIM808 not supporting SSL related commands
I am using SIM808 module. It's working fine with normal MQTT over TCP. But it's not working while implementing secured MQTT. I am sending this command (AT+SSLSETROOT="C:\USER\HENRY_SSL.CRT")...
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Would it be possible to use a GSM without a SIM card?
I would like to reduce the footprint of my PCB (a simple IOT GSM impl.). Given a common GSM such as SIM800/868/900l etc. Would it be possible to completely replace the footprint of a SIM card holder (...
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Problem Understanding how to use Li-Ion battery charger IC
I want to drive a Load that consumes 2A current during data transmission for a concise amount of time, and it can tolerate a maximum of 4.4 volts (SIM800 Series GSM). It works fine with a DC adapter ...
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What does GSM 900/1800 mean?
I was looking at old Nokia 3310 phones, which have GSM 900/1800.
I did some research online from a government website, along with some Google searches, to understand what GSM 900/1800 means. I got a ...
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Battery for GPRS module and voltage regulation
I work on a wearable GSM device powered with a LiPo battery.
I want to use a switching charger with a power path. My GSM module can consume up to 2 amps during data transmission and its working ...
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Ground plane for a GSM spring antenna with 4 layer PCB
We are looking to build a 2G GSM based device with a helical spring antenna like this.
The work in progress layout is as shown below:
We are using a 4 layer PCB with top layer for signal, inner 1 ...
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Problem in capacitor selection
The SIM800L datasheet suggesting a low ESR capacitor for providing a 2 ampere burst current during data transmission.
According to this site MLCC provides the lowest ESR at high-frequency application, ...
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How can I program my mcu stm32f103 to transmit and receive data via a server [closed]
hello I am a beginner and my final project is an alarm system, in fact I use a mcu stm32f103 and I want to transmit the data by a GSM module to a base (to access it by a mobile application) and also ...
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Are there regional constraints with the SIMCom modules? (Eg. SIM7605CE/SIM7600CE)
I recently received a SIMCom Module (Model no. SIM7605CE), shown below.
The item can be (purchased online as well). The device, much like the ones used with Arduinos (like the SIM800L), is supposed ...
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Capacitor for reducing voltage drops
I use gsm module, which makes current bursts up to 2Amps (maybe slightly more). That causes voltage drops about 0.5V on my power supply (I use lipo battery), and than device hangs up or starts ...
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An effective way to knock down GSM on demand
I am building a test rig for a device that has a GSM module to communicate and I want to test how the FW behaves when there is a comms loss and recovery. The GSM module of the device has an antenna ...
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Arduino : send data via satellite (or other solutions) without GSM [closed]
I'm a researcher. I'm looking to build a very tiny embedded system with low power consumption. I must send data from the desert and above the ocean. To do that I think that my single option is to use ...
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Bluetooth antenna problem with SIM800C on my board
I have designed a board with a SIM800C and I have followed all details with its given datasheet. Everything is working well except the Bluetooth that gives very low antenna strength (less than 10cm.)
...
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Is GSM full-duplex?
GSM uses FDD (frequency division duplexing) and provides separate channels for uplink and downlink.
I found however, in this link, that the mobile station does not receive and transmit at the same ...
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Are there any special considerations for extending a UHF-carrying coax wire in a small device?
In the process of doing a repair on a mobile phone, I've tracked down a "no service" issue to an antenna lead inside the case. Specifically, it has detached from the U.FL/MMCX (I'm not sure ...
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