Call us old fashioned, but we feel like when you buy a piece of hardware, the thing should actually function. Now don’t get us wrong, like most of you, we’re willing to put up with the occasional dud so long as the price is right. But when something you just bought is so screwed up internally that there’s no chance it ever could have ever worked in the first place, that’s a very different story.
Unfortunately, that’s exactly what [Majenko] discovered when he tried out one of the USB-C power bank modules he recently ordered. The seemed to charge the battery well enough, but when he plugged a device into the USB output, he got nothing. We don’t mean just a low voltage either, probing with his meter, he became increasingly convinced that the 5 V pin on the module’s IP5306 chip literally wasn’t connected to anything.
Curious to know what had gone wrong, he removed all the components from the board and started sanding off the solder mask. With the copper exposed, his suspicions were confirmed. While they did route a trace from the chip to the via that would take the 5 V output the other side of the board, it wasn’t actually connected.
This is a pretty blatant bug to get left in the board, but to be fair, something similar has happened at least once or twice to pretty much everyone who’s ever designed their own PCB. Then again, those people didn’t leave said flaw in a commercially released module…
The build is a simple mashup, starting with a ZY12PDN USB Power Delivery board. This board talks to a USB-C supply that is compatible with the Power Delivery standard, and tells it to deliver a certain voltage and current output. This is then used to supply power to a pre-built power supply module that handles current limiting, variable voltage output, and all that fancy stuff. It even comes with a screen built-in! Simply slap the two together in a 3D printed case with a couple of banana plugs, and you’re almost done.
All you need then is a USB-C power supply – [Ricardo] uses a portable power bank which allows him to use the power supply on the go. It’s a great alternative to a traditional heavy bench supply, and more than enough for a lot of hobby uses.
Under normal circumstances, if an electronic gadget in your pocket suddenly became hot to the touch, it would be cause for alarm. But not so with the Go Warmer. This lozenge shaped device is not only a USB power bank that can keep your mobile devices topped up, but is also doubles as a miniature heater that the manufacturer claims can bring its surface temperature up to 48 °C (120 °F) for several hours. You can hold in in your hand, put it in your pocket, maybe even sit on it if you’re particularly daring. The possibilities are endless, at least until the 4,000 mAh battery runs down.
For $14.99 USD, the Go Warmer certainly isn’t much of a deal when compared to other battery packs. Even if it does come with a swanky velveteen carrying pouch. But is it a good deal for one that can heat itself up without exploding? Let’s crack this metallic egg and find out.
The electronics side of this build is simple and easy to replicate, with 4 18650 Li-ion cells standard to most high-capacity power banks and an off-the-shelf Fast Charge module serving as the brains of the operation. The beauty of this project however lies in the design of the actual case, completely custom-made from scratch to be 3d printed.
Unlike most power banks, where the outputs stick out to the side and leave the connectors prone to being bumped and damaged, [Franci] engineered his case so the ports are stacked on top and facing inwards. That way, USB plugs are contained within the footprint of the power bank’s body, and therefore protected from bending or snapping off in the socket. He also gracefully provides all instructions needed to make your own, including a wiring guide and a reminder about safety when dealing with battery packs.
In a feat of over-engineering, [Everett Bradford] hacked his power bank to add power monitor via an OLED display to show live current, voltage, temperature, and capacity information. The idea came when he learned about the INA219 chip. The INA219 is a current shunt and power monitor IC with an I²C or SMBUS compatible interface. The device is able to monitor both shunt voltage drop and bus supply voltage, with programmable conversion times and filtering. A programmable calibration value, combined with an internal multiplier, enables direct readouts of current in amperes. An additional multiplying register calculates power in watts.
With impressive miniaturization skills, [Everett] dissembles the Xiaomi Mi power bank and manages to add a custom power monitoring module and an OLED display. Not only that, he replaced the 4 LEDs that were the battery level indicators and actually consume more amps than his board plus the display. While active, the board consumes about 8mA. In sleep mode, it consumes less than 30µA.
The 32×64 OLED display and the custom-made circuit was assembled and tightly fitted into the original case. The power bank now gives readings of the battery charge level in a small graph, numeric current input/output, voltage and temperature. The seamless integration of the display into the power bank makes it look like something that could perfectly have come from a store. This is not your typical DIY power bank nor a gigantic 64 cells power bank. It is a precise and careful modification of an existing product, adding value, functionality, and dare I say it, style: an awesome hack!
We can see [Everett] process in the following video:
A fixture on many British high streets are pound shops. You may have an equivalent wherever in the world you are reading this; shops in which everything on sale has the same low price. They may be called dollar stores, one-Euro stores, or similar. In this case a pound, wich translates today to a shade under $1.24.
Amid the slightly random selection of groceries and household products are a small range of electronic goods. FM radios, USB cables and hubs, headphones, and mobile phone accessories. It was one of these that caught [Julian Ilett]’s eye, a USB power bank. (Video embedded below.)
You don’t get much for a quid, and it shows in this product. A USB cable that gets warm at the slightest current, a claimed 800 mA of output at 5V from a claimed 1200 mAh capacity, and all from an 18650 Li-ion cell of indeterminate origin. The active component is an FM9833E SOIC-8 switching regulator and charger (220K PDF data sheet, in Chinese).
A straightforward teardown of a piece of near-junk consumer electronics would not normally be seen as something we’d tempt you with, but [Julian] goes on to have some rather pointless but entertaining fun with these devices. If you daisy-chain them, they can be shown to have the properties of rudimentary digital logic, and in the video we’ve put below the break it is this that he proceeds to demonstrate. We see a bistable latch, a set-reset latch, a very slow astable multivibrator, and finally he pulls out a load more power banks for a ring oscillator.
If only [MacGyver] had found himself trapped in a container of power banks somewhere from which only solving a complex mathematical conundrum could release him, perhaps he could have fashioned an entire computer! The best conclusion is the one given at the end of the video by [Julian] himself, in which he suggests (and we’re paraphrasing here) that if you feel the idea to be unworthy of merit, you can tell him so in the comments.
No, not a real fox! [KM4EFP] is a ham radio operator with a passion for fox hunting, which is an event where several radio operators attempt to find a broadcasting beacon (a “fox”) using radio direction finding techniques. [KM4EFP] has just built his own portable fox using a Raspberry Pi in a very well-built enclosure.
Since the fox could be outside for a while, the project was housed in a reasonably weatherproof ammunition case. A mount for an antenna was attached to the side, and it is hooked up to a GPIO pin on the Raspberry Pi. The entire device is powered by a 6000 mAh battery pack which allows the fox to broadcast long enough to be found.
The software running on the Raspberry Pi is very similar to the Pi FM transmitter program but it is specially made for ham radio broadcasting instead. Almost no extra hardware is needed to get the Pi broadcasting radio, as these software packages can drive the antenna directly from the GPIO pin. This is a great twist on the standard FM transmitter that ham radio enthusiasts everywhere can use to start finding those wily foxes!