Questions tagged [cellphone]
Questions regarding cellphones, or cellular devices. Please note that repair questions are often closed for failing to follow the Scope of the Site as described in the FAQ.
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How can I record with this old fashioned mono microphone? [closed]
I have this microphone that comes with a 3.5mm mono jack connector.
When I plug it in to my laptop or my phone it won't work, and I believe the "mono" part is the problem. What do I need to ...
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Hooking up D-cell batteries to charge phones
I am trying to set up a disposable battery pack to recharge phones, I was able to find online a female usb cable connected to 4 AA that charges fine. when testing with 8 d-cell in series, charging 3 ...
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What would be the Maximum ERIP of cellphone in absence of 23dBm 3gpp restrictions? [closed]
Consider a 5g cellphone with 4×4 MIMO antaenna (4 transmitters),wifi antaenna,& Bluetooth antaenna. Considering the 3gpp guidelines, current EIRP is set to maximum of 23dBm, which is maintained by ...
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Why solid state capacitors?
I've been looking through multiple cellphone chargers and I have noticed that they all use solid state capacitor for the output capacitor of the switching power supply (flyback converter).
Is there ...
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Wireless phone charging: ways to mitigate distance (charging gap) limitations?
I'd like to use a nice, thick otterbox defender style case, and keep wireless charging, but not shell out almost $100 for the actual otterbox defender case.
Those cases are sturdy and protect the ...
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Real World Range of C-Band (3.7Ghz) versus EBS/BRS (2.5Ghz) mid-band 5G
I am aware that with all things being equal, lower frequencies propagate better. Thus, T-Mobile’s 2.5Ghz spectrum should have better range than AT&T’s and Verizon’s 3.7Ghz spectrum. T-Mobile ...
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What type of embedded sytem is used in a mobile phone(cell phone)?
What type of embedded system is used in a mobile?Is it a microcontroller, FPGA or a DSP
According to my understanding the basic and simple mobile phones like nokia 3310 used microcontroller since ...
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What indicators can I use to decide whether a power bank which I am interested in buying will appropriately regulate current and voltage?
Anker, one of the largest manufacturers of power banks, often indicates in its ads that the product in question uses a specific system, MultiProtect, to avoid stressing the phone battery which is ...
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Why isn't it easy to put an ampere-meter into any battery driven electronics?
I can buy a cheap multimeter which has an ampere-meter function. Great.
Battery driven computer equipment like laptops and cellphones are complex, and for power / battery management I suppose an ...
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Do cell-phone base station antennas emit the same power as cell phones?
Do cell-phone base station antennas emit the same power of waves as from a cell phone?
I would assume so because both waves need to travel the same distance, right?
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Is it safe to use any arbitrary charger for a smartphone? [closed]
Today, most smartphones have USB-C chargers, and this allows to use any charger with any phone. The issue I have, though, is that these chargers have different amperage, different wattage and so on. ...
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Send image using RPI to phone using Bluetooth [closed]
I'm looking to send an image file from a RPI Zero (or RPI4) to a mobile phone. The image file will be sent after pressing a push-button.
The connection between the RPI and the phone is only Bluetooth (...
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How can I use the same microphone for an amplifier and a mobile phone?
This is my first question on this forum, and I would like to say that I am learning electronics, and I am not an expert by any means.
I am currently trying to realize a small project using a LM386 to ...
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Why do cell phone chargers drop speed when multiple devices are connected?
What are the 'limitations' that prevent a wall charger from charging multiple devices at their maximum power?
Let's say I have a 4-port cell phone charger that is rated at an unknown wattage. When I ...
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Making a "Power Wall" battery out of cell phone batteries
Cellphone batteries varies in shape and size, and most importantly, in battery chemistries. Some chemistries result in a nominal voltage under load of 3.7 V with a full charge at 4.2 V (same as 18650),...
