A LiPo Cell Makes A 4AA Pack For A GameBoy

July 31, 2021 by Jenny List 14 Comments

Electronic toys of yesteryear were fantastic objects of desire, but came with the fatal flaw of requiring batteries. Batteries that cost more than the average youngster’s pocket money and for which the pestered parent were usually unwilling to fork out every couple of days to support an incessant playing habit. It’s something [Sen] has addressed for the Nintendo Game Boy, and rather than cutting the device up and soldering wires, the result is a unit that neatly slots into the existing 4AA battery enclosure.

The Nintendo rechargable Game Boy pack. — Much more convenient than Nintendo’s own effort!

Electrically it’s a simple case of wiring up an Adafruit module and a pouch cell, but that’s not the essence of the job in this case. Instead a huge quantity of work and iteration has gone into CAD design to the perfect-fitting pack. It’s sure to be a boon for today’s Game Boy player, but much more than that it should be of interest to owners of far more devices that take four AA cells. Most of us probably keep a few packs of AAs for just those moments, perhaps meanwhile something like this could be a handy thing to have instead.

More traditional conversions resort to extreme measures, as with this Game Boy Color.

A Battery To Add A Tingling Sensation To Your Tweets

September 27, 2020 by Sven Gregori 28 Comments

Internet-connected sex toys are a great way to surprise your partner from work (even the home office) or for spicing up long-distance relationships. For some extra excitement, they also add that thrill of potentially having all your very sensitive private data exposed to the public — but hey, it’s not our place to kink-shame. However, their vulnerability issues are indeed common enough to make them regular guests in security conferences, so what better way to fight fire with fire than simply inviting the whole of Twitter in on your ride? Well, [Space Buck] built just the right device for that: the Double-Oh Battery, an open source LiPo-cell-powered ESP32 board in AA battery form factor as drop-in replacement to control a device’s supply voltage via WiFi.

Battery and PCB visualization — Double-Oh Battery with all the components involved

In their simplest and cheapest form, vibrating toys are nothing more than a battery-powered motor with an on-off switch, and even the more sophisticated ones with different intensity levels and patterns are usually limited to the same ten or so varieties that may eventually leave something to be desired. To improve on that without actually taking the devices apart, [Space Buck] initially built the Slot-in Manipulator of Output Levels, a tiny board that squeezed directly onto the battery to have a pre-programmed pattern enabling and disabling the supply voltage — or have it turned into an alarm clock. But understandably, re-programming patterns can get annoying in the long run, so adding WiFi and a web server seemed the logical next step. Of course, more functionality requires more space, so to keep the AA battery form factor, the Double-Oh Battery’s PCB piggybacks now on a smaller 10440 LiPo cell.

But then, where’s the point of having a WiFi-enabled vibrator with a web server — that also happens to serve a guestbook — if you don’t open it up to the internet? So in some daring experiments, [Space Buck] showcased the project’s potential by hooking it up to his Twitter account and have the announcement tweet’s likes and retweets take over the control, adding a welcoming element of surprise, no doubt. Taking this further towards Instagram for example might be a nice vanity reward-system improvement as well, or otherwise make a great gift to send a message to all those attention-seeking people in your circle.

All fun aside, it’s an interesting project to remote control a device’s power supply, even though its application area might be rather limited due to the whole battery nature, but the usual Sonoff switches may seem a bit unfitting here. If this sparked your interest in lithium-based batteries, check out [Lewin Day]’s beginner guide and [Bob Baddeley]’s deeper dive into their chemistry.

Pocket High Voltage Generator Becomes Great Test Tool

October 8, 2018 by Donald Papp 4 Comments

[The LED Artist] often found a need for a relatively high voltage (100 to 200 Volt) but low current DC power supply, and it turns out that a small HV generator that uses a single AA cell only took about an hour to make. The device ended up being a pretty handy tool for testing things like LED filaments (which have a forward voltage of over 60 V), or even neon and nixie tubes.

The device’s low current means that nixie and neon elements won’t light up very brightly, but they will light up enough to verify function and operation. [The LED Artist] reports that touching the output terminals of the generator only causes a slight tingling sensation.

Open-circuit voltage generated from a single AA cell is about 200 V, but that voltage drops rapidly under any kind of load. Even regular LEDs can be safely lit with the circuit, with less than a milliamp being supplied at the two to three volts at which most regular LEDs operate.

[The LED Artist] fit the device into a two-AA battery holder, with a single AA cell on one side and the circuit in the other, and says it’s one of the more useful tools they’ve ever made. LED filaments are fairly common nowadays, but if they intrigue you, don’t forget that [Mike Harrison] covered everything you need to know about experimenting with them.

A Better Battery Arduino

October 1, 2018 by Kerry Scharfglass 5 Comments

We’ve seen [Johan]’s AA-battery-sized Arduino/battery crossover before, but soon (we hope!) there will be a new version with more MIPS in the same unique form factor! The original Aarduino adhered to classic Arduino part choices and was designed to run as the third “cell” in a 3 cell battery holder to relay temperature readings via a HopeRF RFM69CW. But as [Johan] noticed, it turns out that ARM development tools are cheap now. In some cases very cheap and very open source. So why not update an outstanding design to something with a little more horsepower?

The Aarduino Zero uses the same big PTH battery terminals and follows the same pattern as the original design; the user sticks it in a battery holder for power and it uses an RFM69CW for wireless communication. But now the core is an STM32L052, a neat low power Cortex-M0+ with a little EEPROM onboard. [Johan] has also added a medium size serial flash to facilitate offline data logging or OTA firmware update. Plus there’s a slick new test fixture to go along with it all.

So how do you get one? Well… that’s the rub. It looks like when this was originally posted at the end of 2017 [Johan] was planning to launch a Crowd Supply campaign that hasn’t quite materialized yet. Until that launches the software sources for the Zero are available, and there are always the sources from the original Aarduino to check out.

Need A Night-Light?

September 19, 2017 by Lauren Faris 36 Comments

[Scott] created an LED candle in preparation for the big mac daddy storm (storms?) coming through. Like millions of other people in Florida, he was stuck at home with his roommates when an oncoming hurricane headed their way. Worrying about blundering about in the dark when the power inevitably went out, they set off to gather up all of the candles they had lying around. Realizing the monstrous pile of candles and matches looked more and more like a death wish, the decision was made to create a makeshift light out of what components they had on hand. Now, not having access to any outside sources for parts means that you are going to have a bare bones model.

That being said, this straightforward light only takes a couple of seconds to put together. Jury rig a couple of AA or AAA batteries up, then slap on a resistor, LED, and jumper to get that sucker running. Wrap electrical tape around the whole thing, or even try duct tape, whatever gets the job done. A little paper hat on top of it will diffuse the light and bada bing, bada boom, you’re all done. Generally though, soldering directly onto a battery is not a wise idea. So, if you want to get fancy, perhaps a better alternative is to have a battery casing as shown below.

This LED candle is a clear option if your home isn’t a micro warehouse for electronic components (apparently it is frowned upon to clog up your garage for projects), and you have limited time. However, if you have a number of extra minutes lying around before your windows blow in, see if you can top the brightest flashlight ever made (thus far). Continue reading “Need A Night-Light?” →

Hackaday Links: September 3, 2017

September 3, 2017 by Brian Benchoff 35 Comments

The TI-83, TI-84, and TI-86 have been the standard graphing calculators in classrooms for two decades. This is the subject of an xkcd. Now, hopefully, there’s a contender for the throne. Numworks is a graphing calculator that looks like it was designed in at least 2006 (so very modern), and apparently, there’s a huge community behind it.

Juicero is shutting down. No one could have seen this one coming. The Juicero was a $700 press that turned proprietary, DRM’ed juice packs into juice and garbage. It was exquisitely engineered, but it turns out very few people want to spend thousands of dollars per year on DRM’ed juice. Oh, since the Juicero phones home, those $700 presses probably won’t work in the future.

Are you in the Bay area? Do you need test equipment? There’s a gigantic auction happening somewhere around San Jose. [Dave] tipped everyone off to this one, and this auction is pretty freakin’ spectacular. Spectrum analyzers, signal gens, a ‘mega zoom’ oscilloscope, and 4-channel, 500 MHz scopes for $50. There are a thousand lots in this auction. It’s nuts.

Everybody loves PCB art, and [Uri] has a guide for designing custom, functional electronic circuit boards. The toolchain used in this guide is Inkscape and KiCad, with blinky hearts, blinky pandas, and other blinky PCBs.

This one is a little out there even for us. Here’s how you build your own AA batteries. It’s a dozen #10 copper washers, a dozen or so #10 zinc washers, some cardboard, vinegar, salt, and some heat shrink tubing. The assembly of this battery is exactly what you would expect, and yes, it does work. Here’s the thing, though: The very crude tests suggest these batteries have a capacity of about 800-1000 mAh, which is far more than we would expect. Who has a programmable load and wants to do a few experiments? Also, these batteries are ‘rechargeable’ by taking them apart, sanding the crud off each washer, and adding new electrolyte.

[Jan] has made a name for himself stuffing synthesizers into tiny little microcontrollers. The latest project is the Infinity37, a polyphonic synth with MIDI, envelopes, and a whole bunch of cool stuff. Check out the video.

[rctestflight] is building a solar powered aircraft. It’s has a beautiful wing studded with solar panels. The latest flight was four hours, long enough to make piloting a plane through some FatSharks extremely tedious. Future developments will probably include a MPPT charging solution, and probably an autopilot.

Hacklet 26 – Arduino Projects

December 12, 2014 by Adam Fabio 8 Comments

Arduino is one of those boards that has become synonymous with hacking and making. Since its introduction in 2005, over 700,000 official Arduino boards have been sold, along with untold millions of compatible and clone boards. Hackers and makers around the world have found the Arduino platform a cheap and simple way to get their projects off the ground. This weeks Hacket focuses on some of the best Arduino based projects we’ve found on Hackday.io!

[Niazangels] gets the ball – or ballpoint pen – rolling with Roboartist, a robot which creates line drawings. Roboartist is more than just a plotter though. [Niazangels] created a custom PC program which creates line drawings from images captured by a webcam. The line drawings are converted to coordinates, and sent to an Arduino, which controls all the motors that move the pen. [Niazangels] went with Dynamixel closed loop servo motors rather than the stepper motors we often see in 3D printers.

[Peter Edwards] is preserving the past with Tapuino, the $20 C64 Tape Emulator. Plenty of programs for the Commodore 64, 128, and compatibles were only distributed on tape. Those tapes are slowly degrading, though the classic Commodore herdware is still going strong. Tapuino preserves those tapes by using an Arduino nano to play the files from an SD card into the original Datasette interface. [Peter] also plans to add recording functionality to the Tapuino, which will make it the total package for preserving your data. All that’s missing is that satisfying clunk when pressing the mechanical Play button!

[Dushyant Ahuja] knows what time it is, thanks to his Infinity Mirror Clock. This clock tells time with the help of some WS2812B RGB LED. [Dushyant] debugged the clock with a regular Arduino, but when it came time to finish the project, he used an ATmega328 to create an Arduino compatible board from scratch. Programming is easy with an on-board Bluetooth module. [Dushyant] plans to add a TFT lcd which will show weather and other information when those power-hungry LEDs are switched off.

[IngGaro] built an entire home alarm system with his project Arduino anti-theft alarm shield. [IngGaro] needed an alarm system for his home. That’s a lot to ask of a standard ATmega328p powered Arduino Uno. However, the extra I/O lines available on an Arduino Mega2560 were just what the doctor ordered. [IngGaro] performed some amazing point-to-point perfboard wiring to produce a custom shield that looks and works great! The alarm can interface with just about any sensor, and can be controlled via the internet. You can even disarm the system through an RFID keycard.

Want MORE Arduino in your life? Check out our curated Arduino List!

That’s about all the millis() we have for this weeks Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!