Questions tagged [modem]
A modem (modulator-demodulator) is a device used to transmit and receive digital data over an analog communications channel. Common examples are PC modems that use an analog telephone line and wireless modems that use RF (radio frequency).
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STM32 Over-The-Air update with SIM7682E LTE modem
I have a need to add an Over-The-Air firmware update feature to my project. It is based on STM32F103CBT6 and SIMCOM SIM7682E LTE modem.
The main idea is to connect to the FTP server or get the file ...
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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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Help me identify this unknown SMD transistor
Could you help me identify this transistor?
I have searched every SMD code decoder and can't find the exact type of this transistor:
It apparently has CCE1X written on it, and has a SOT-23-6 package ...
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Data logging on a SIM5320
One of my SIM5320 devices is using a lot more data than before while sending a POST message to a web server. I like to see what connections the SIM5320 is establishing, but i don't know how. What is ...
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How to access modem inside Android mobile from a PC through USB cable? [closed]
Every mobile has a modem inside it, which allows dialing phone numbers and connecting to data/GPRS.
I guess we can send AT commands to all modems in phones.
So if I tear down an Android phone e.g. a ...
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Problem with GPS old location [closed]
I wrote a GPS driver which sends and reads AT commands. I send the AT+CGPS=1,1 command to get the GPS location and if there is no answer I send ...
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Sizing the DC/DC inductor for only momentary high currents
My DC/DC setup is going to power a GSM modem. The behavior of these modems is that they typically consume only a few tens of milliamps, but when transmitting they are drawing 2A for microseconds. On ...
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SIM7080 UART Noise interfacing with PIC18F4550
I'm working on a project where I read data over Modbus line and send it in the cloud service through a SIM7080 CATM modem. I'm using PIC18F4550 as MCU.
As that PIC18F has just one UART module, I'm ...
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Two devices sharing the same coaxial cable, what frequency channel should I chose? [closed]
The 2-stories house is equipped with a coaxial cable that has wall plugs in 1st and 2nd floors (it's also connected to the antenna on the roof).
Our IAP installed a modem for Internet (Arris CM820C) ...
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FTDI cable (TTL-232R-3V3) mixed up wires [closed]
At the beginning of the measuring task, I mixed up wires connecting my FTDI USB to UART cable (TTL-232R-3V3) with serial connector header pins (TX/RX/VCC/Gnd) on device (data modem). I didn't ...
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Jumps in signal/noise ratio on problematic VDSL connection
(I am not sure this question is on-topic here. It seemed off-topic in networking because the connection is not in a professionally managed environment. Perhaps super user would be a better fit? But ...
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Problem with using power bank for modem with dc dc booster
I want to run a modem that needs 12 volts with a power bank.
I've used a DC-DC booster to increase the voltage of my power bank which is 5 volts up to 12 volts and there is no problem with that.
After ...
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Providing phone line current for direct modem-modem communication
In order to directly connect two modems without a real phone line, one option is to put a battery inline (to create the current loop?). Most information I've found about this relates to the SEGA ...
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Could power cycling a modem 24 times a day for over 3 years (>30,000 times) cause the modem to lose its settings? [closed]
Could power cycling a modem 24 times a day with it being on for 10mins at a time for over 3 years (>30,000 times) cause the modem to lose its setting and revert to factory?
This modem.
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What connector is this? (Inside a wifi modem)
I was about to attach an antenna to my 4g modem and thus trying to identify which connector is there on my modem board and i found this connector (4 of them, 2 for 4g and 2 for wifi).
I tried ...
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