$54 ZMI MF855 is Both a Power Bank and a Portable 4G Wireless Router

ZMI MF855 4G Router Power Bank

Tiny routers usually come with at least one USB port that allows you to connect a 3G or 4G cellular dongle, and since it’s often used on the go, or as a backup solution it makes sense to have a battery in the router as well, as was the case for Marstek MPR-N9 I covered way back in 2013. Xiaomi ZMI MF855 portable wireless router offers the same function but with an integrated 4G modem, a larger 7,800 mAh battery that can also be used to charge your other device. The router looks like a standard power bank from the outside. ZMI MF855 router key features: Cellular Connectivity 4G/3G and 2G networks Micro SIM card socket FDD-LTE bands – B1 1800 B3 2100 B7 2600 MHz TDD-LTE bands – B38 1900 B39 2300 B40 2500 B41 2600MHz WCDMA bands – B1 850 B2 900 B5 1900 B8 2100 MHz WiFi […]

ATORCH USB PD Power Meter Comes with USB type-C, type-B, and type-A Ports

ATORCH J7-c

Most smartphones are charged over a USB port, and many single board computers are powered by a micro USB or USB type-C port, and USB power meters such as USB Charger Doctor can be useful to evaluate phone chargers, as well as measure power consumption of SBCs. With the launch of the USB type-C connector and features such as USB PD (Power Delivery), old USB power meters are not adapted to the new standard since the connector and most importantly voltages are different, so we need USB PD compatible meters like Satechi USB Type-C power meter. Today, I decided to look for more options on Aliexpress, and you’ll find many USB-C power meters with the cheapest models going for under $5 shipped. However,  ATORCH J7-c model caught my attention since it supports both USB type-C, micro USB type-B, and USB type-A power sources, so you can keep using the same […]

Raspberry Pi PoE HAT Launches, But Refunds Offered due to Power Issues

Raspberry Pi 3+ with PoE HAT

The Raspberry Pi foundation has launched a good number of boards and  accessories, and although some people will question some of the design choices, their boards were fairly bug-free hardware-wise at launch, except for minor issues like the board rebooting while taking a photo with a Xenon flash. Recently they also had performance issues with Gigabit Ethernet in the  Raspberry Pi 3 B+ board, but that looks like more of a software issue. The Raspberry Pi PoE HAT announced with Raspberry Pi 3B+, but launched at the end of August for $20,  however suffers from a more serious issue as it somehow limits USB current to 200mA instead of the usual 500mA, meaning that’s fine with USB keyboard and mouse, but as soon as you connect more power hungry peripherals like a USB hard drive, all hell breaks loose. Let’s check out the specifications first: 802.3af PoE Fully isolated switched-mode […]

CHOETECH 24W Foldable Solar Charger Review

Foldable Solar Charger Charging Smartphone

A short while ago, I wrote about  a tri-panel waterproof solar power bank that delivers up to 4 Watts and comes with 10,000 mAh capacity. I’ve now received a sample of a somewhat similar product, except CHOETECH told me it can deliver up to 24 Watts, which should be more suitable for charging devices like smartphone daily. CHOETECH 24W Solar Charger Unboxing The gadget is supposed to be fitted on larger backpacks as we’ll see below, but it comes in a relatively small package. The thing just looks like some purse or wallet out of the box. Once it’s unfolded we’ll see four solar panel, six hoops around the design, and some pouch / pocket on the right. The “junction box” includes a micro USB to USB cable, some silica gel, and four metal hoops to hook around some of the 6 fabric hoops The text on the photo above […]

Embedded Linux Conference Europe & OpenIoT Summit Europe 2018 Schedule

Embedded Linux Conference OpenIOT Summit Europe 2018

The Embedded Linux Conference & OpenIoT Summit 2018 took place in March of this year in the US, but the European version of the events are now planned to take place on October 21-24 in Edinburg, UK, and the schedule has already been released. So let’s make a virtual schedule to find out more about some of interesting subjects that are covered at the conferences. The conference and summit really only officially start on Monday 22, but there are a few talks on Sunday afternoon too. Sunday, October 21 13:30 – 15:15 – Tutorial: Introduction to Quantum Computing Using Qiskit – Ali Javadi-Abhari, IBM Qiskit is a comprehensive open-source tool for quantum computation. From simple demonstrations of quantum mechanical effects to complicated algorithms for solving problems in AI and chemistry, Qiskit allows users to build and run programs on quantum computers of today. Qiskit is built with modularity and extensibility […]

Pi-Zero-UpTime is an UPS for Raspberry Pi Boards and Clones

Pi-Zero-UpTime UPS for Raspberry Pi

Since for a headless Raspberry Pi it makes no sense to use a large UPS (Uninterruptible Power Supply) to keep it running in case of power failure,  I bought and tested a Raspberry Pi battery kit a couple of years ago. The kit included an acrylic case,  a battery charging board, and LiPo battery and it worked most of the time as a UPS. “Most of the time” means the switch from mains to battery would not occur fast enough maybe 10% of the time (it depends on the load), so the Raspberry Pi board would reboot. The kit also did not include a GPIO / I2C interface to report the charge level of the battery, so you would not be able to safely power the board when the battery is almost fully depleted. In recent years, it’s become more and more difficult to get batteries shipped from overseas, so […]

Banana Pi BPI-M2+ V1.2 Board Improves Power Management

When people decided which development board to purchase for their project / use case(s), the often look at the processor, memory, storage, and the external ports, as well as I/Os. However, very few people look at the PMIC (Power Management IC) on the board, as it’s normally an afterthought. Development boards can work without PMIC, instead relying on a single fixed voltage, and for many people that may be good enough, but for more demanding tasks it may lead to either lower performance or overheating issues. Modern processor all rely on DVFS ( Dynamic Voltage and Frequency Scaling) in order to adjust both the voltage and frequency of the processor depending on the load. This is done to optimize power consumption and/or manage the power budget, and overheating may lead to CPU throttling, where the system lowers the frequency and/or operating voltage in  order to avoid damaging the processor. I’m […]

UM25C is a Better USB Power Meter with built-in Display, Bluetooth, and Android & Windows Apps

UM25C

Products such as USB Charger Doctor are good way to test your USB chargers or cables, as well as checking the power consumption of USB powered development boards. You just plug them into a USB port, and connect the load, and you’ll see the real-time voltage and current shown on an LED display. Those do the job, but I’ve just been made aware of UM25C USB meter tester that improves a lot on the concept with a dot matrix display capable of showing charts, and Bluetooth connectivity to send the data to Android or Windows devices. UM25C specifications: Display 1.44″ color LCD display 0-5 brightness setting Auto screen off time – 0 to 9 minutes Refresh rate – 2Hz Measurement Range & Accuracy Voltage – 4-24.000V ±0.5‰ + 2digits Current –  0-5.0000A ±1‰ + 4 digits Capacity – 0-99999mAh Energy accumulation – 0-99999mWh Load impedance – 0.8Ω-9999.9Ω Time range – […]