DIY Magsafe Charger Feeds Off 12 V Solar Battery

April 19, 2020 by Donald Papp 18 Comments

[Steve Chamberlin] has a spiffy solar-charged 12 V battery that he was eager to use to power his laptop, but ran into a glitch. His MacBook Pro uses Apple’s MagSafe 2 connector for power, but plugging the AC adapter into the battery via a 110 VAC inverter seemed awfully inefficient. It would be much better to plug it into the battery directly, but that also was a problem. While Apple has a number of DC power adapters intended for automotive use, none exist for the MagSafe 2 connector [Steve]’s mid-2014 MacBook Pro uses. His solution was to roll his own MagSafe charger with 12 VDC input.

Since MagSafe connectors are proprietary, his first duty was to salvage one from a broken wall charger. After cleaning up the wires and repairing any frayed bits, it was time to choose a DC-DC converter to go between the MagSafe connector and the battery. The battery is nominally 12 volts, so the input of the DC-DC converter was easy to choose, but the output was a bit uncertain. Figuring out what the MagSafe connector expects took a little educated guesswork.

The original AC adapter attached to the charger claimed an output of 20 volts, another Apple adapter claimed a 14.85 V output, and a third-party adapter said 16.5 volts. [Steve] figured that the MagSafe connectors seemed fine with anything in the 15 to 20 V range, so it would be acceptable to use a 12 V to 19 V DC-DC boost converter which he had available. The result worked just fine, and [Steve] took measurements to verify that it is in fact much more efficient than had he took the easy way out with the inverter.

MagSafe has been displaced by USB-C nowadays, but there are plenty of MagSafe devices still kicking around. In a pinch, keep in mind that a little bit of filing or grinding is all that’s needed to turn MagSafe 1 into MagSafe 2.

An Adapter To Solve Your ESP-01 Breadboard Woes

April 4, 2020 by Tom Nardi 9 Comments

The ESP-01 launched the ESP8266 revolution back in 2014, and while today you’re far more likely to see somebody use a later version of the chip in a Wemos or NodeMCU development board, there are still tasks the original chip is well suited for. Unfortunately, they can be tricky to use while prototyping because they aren’t very breadboard friendly, but this adapter developed by [Miguel Reis] can help.

Of course, the main issue is the somewhat unusual pinout of the ESP-01. Since it was designed as a daughter board to plug into another device, the header is too tight to fit into a breadboard. The adapter that [Miguel] has come up with widens that up to the point you can put it down the centerline of your breadboard and have plenty of real estate around it.

The second issue is that the ESP-01 is a 3.3 V device, which can be annoying if everything else in the circuit is running on 5 V. To get around this, the adapter includes an SPX3819 regulator and enough capacitors that the somewhat temperamental chip gets the steady low-voltage supply it needs to be happy.

[Miguel] has released the schematics and board files so you can spin up your own copy of the adapter, but they’re also available for around $3 USD from his Tindie store.

Designing Printed Adapters For Power Tool Batteries

March 30, 2020 by Tom Nardi 26 Comments

Unless you’re particularly fond of having multiple types of batteries and chargers, you’d do well to make sure all your portable power tools are made by the same company. But what do you do if there’s a tool you really need, but your brand of choice doesn’t offer their own version of it? Rather than having to buy into a whole new tool ecosystem, you might be able to design your own battery adapter.

Note the locking tab that’s been printed separately.

As [Chris Chimienti] explains in the video after the break, the first thing you’ve got to do (beyond making sure the voltages match) is take some careful measurements of the connectors on your batteries and tools. His goal was to adapt a Milwaukee M12 battery to Makita CXT tool, so if you happen to have that same combination of hardware you can just use his STLs. Otherwise, you’ll be spending some quality time with a pair of calipers and a notepad.

Once the interfaces have been designed and printed, they are wired together and mounted to opposite ends of the center support column. In theory you’d be done at this point, but as [Chris] points out, there’s a bit more to it than just wiring up the positive and negative terminals. Many tools use thermistors in the batteries for thermal protection purposes, and when the tool doesn’t get a reading from the sensor, it will likely refuse to work.

His solution to the problem is to “hotwire” the thermistor lead on the battery connector with a standard resistor of the appropriate value. This will get the tool spinning, but obviously there’s no more thermal protection. For most homeowner DIY projects this probably won’t cause a problem, but if you’re a pro who’s really pushing their tools to the limit, this project might not be for you.

Of course, this isn’t the first time we’ve seen somebody adapt batteries from different brands to work on their tools. It’s a common enough problem once you start building up a workshop, although you could always avoid it by building all your own tools.

Continue reading “Designing Printed Adapters For Power Tool Batteries” →

Faking Your Way To USB-C Support On Laptops Without It

March 27, 2020 by Mike Szczys 42 Comments

Is there no end to the dongle problem? We thought the issue was with all of those non-USB-C devices that want to play nicely with the new Macbooks that only have USB-C ports. But what about all those USB-C devices that want to work with legacy equipment?

Now some would say just grab yourself a USB-C to USB-A cable and be done with it. But that defeats the purpose of USB-C which is One-Cable-To-Rule-Them-All^[1]. [Marcel Varallo] decided to keep his 2011 Macbook free of dongles and adapter cables by soldering a USB-C port onto a USB 2.0 footprint on the motherboard.

How is that even possible? The trick is to start with a USB-C to USB 3 adapter. This vintage of Macbook doesn’t have USB 3, but the spec for that protocol maintains backwards compatibility with USB 2. [Marcel] walks through the process of freeing the adapter from its case, slicing off the all-important C portion of it, and locating the proper signals to route to the existing USB port on his motherboard.

[1] Oh my what a statement! As we’ve seen with the Raspberry Pi USB-C debacle, there are actually several different types of USB-C cables which all look pretty much the same on the outside, apart from the cryptic icons molded into the cases of the connectors. But on the bright side, you can plug either end in either orientation so it has that going for it.

Classic Macintosh Gets An IPad Infusion

March 23, 2020 by Tom Nardi 19 Comments

We know the classic Mac fans in the audience won’t be happy about this one, but the final results are simply too clean to ignore. With a laser-cut adapter and a little custom wiring, [Travis DeRose] has come up with a repeatable way to modernize a Compact Macintosh (Plus, SE, etc) by swapping out all of its internals for an iPad mini.

He goes over the whole process in the video after the break, while being kind enough to spare our sensitive eyes from having to see the Mac’s enclosure stripped of its original electronics. We’ll just ~~pretend~~ hope that the computer was so damaged that repair simply wasn’t an option.

Anyway, with a hollow Mac in your possession, you can install the adapter that allows the iPad to get bolted in place of the original CRT monitor. You won’t be able to hit the Home button anymore, but otherwise it’s a very nice fit.

Those with some first hand iPad experience might be wondering how you wake the tablet up once the Mac is all buttoned back up. That’s an excellent question, and one that [Travis] wrestled with for awhile. In the end he came up with a very clever solution: he cuts into a charging cable and splices in a normally-closed momentary push button. Pushing the button essentially “unplugs” the iPad for a second, which just so happens to wake it up. It’s an elegant solution that keeps you from having to make any modifications to that expensive piece of Apple hardware.

If there’s one thing we’re not thrilled with, it’s the empty holes left behind where the ports, switches, and floppy drive were removed. As we’ve seen in the past, you can simply cut the ports off of a motherboard and glue them in place to make one of these conversions look a little more convincing. If you’re going to do it, might as well go all the way.

Continue reading “Classic Macintosh Gets An IPad Infusion” →

Use Your Earbud’s Media Controls On Your Laptop With This Useful Dongle

November 9, 2019 by Gerrit Coetzee 3 Comments

[David] sends in his very nicely designed “Thumpware Media Controller” that lets your mobile phone headphones control the media playback on your PC.

We realize that some PCs have support for the extra pins on cellphone earbuds, but at least some of us have experienced the frustration (however small) of habitually reaching up to touch the media controls on our earbuds only to hear the forlorn click of an inactive-button. This solves that, assuming you’re still holding on to those 3.5mm headphones, at least.

The media controls are intercepted by a PIC16 and a small board splits and interprets the signals into a male 3.5mm and a USB port. What really impressed us is the professional-looking design and enclosure. A lot of care was taken to plan out the wiring, assembly, and strain relief. Overall it’s a pleasure to look at.

All the files are available, so with a bit of soldering, hacking, and careful sanding someone could put together a professional looking dongle for their own set-up.

You Need A Cyberdeck, This Board Will Help

August 16, 2019 by Tom Nardi 8 Comments

In 1984, William Gibson’s novel Neuromancer helped kick off the cyberpunk genre that many hackers have been delighting in ever since. Years before Tim Berners-Lee created the World Wide Web, Gibson was imagining worldwide computer networks and omnipresent artificial intelligence. One of his most famous fictional creations is the cyberdeck, a powerful mobile computer that allowed its users to navigate the global net; though today we might just call them smartphones.

While we might have the functional equivalent in our pockets, hackers like [Tillo] have been working on building cyberdecks that look a bit more in line with what fans of Neuromancer imagined the hardware would be like. His project is hardly the first, but what’s particularly notable here is that he’s trying to make it easier for others to follow in his footsteps.

There’s a trend to base DIY cyberdecks on 1980s vintage computer hardware, with the logic being that it would be closer to what Gibson had in mind at the time. Equally important, the brutalist angular designs of some of those early computers not only look a lot cooler than anything we’ve got today, but offer cavernous internal volume ripe for a modern hardware transfusion. Often powered by the Raspberry Pi, featuring a relatively small LCD, and packed full of rechargeable batteries, these cyberdecks make mobile what was once anchored to a desk and television.

[Tillo] based his cyberdeck on what’s left of a Commodore C64c, reusing the original keyboard for that vintage feel. That meant he needed to adapt the keyboard to something the Raspberry Pi could understand, for which some commercially available options existed already. But why not take the idea farther for those looking to create their own C64c cyberdecks?

He’s currently working on a new PCB specifically designed for retrofitting one of these classic machines with a Raspberry Pi. The board includes niceties like a USB hub, and should fill out some of those gaping holes left in the case once you remove the original electronics. [Tillo] has already sent the first version of his open source board out for fabrication, so hopefully we’ll get an update soon.

In the meantime, you might want to check out some of the other fantastic cyberdeck builds we’ve covered over the last couple of years.