World’s Worst I/O Dock Doesn’t Deserve Elegant Fix

March 19, 2022 by Donald Papp 63 Comments

Even spendy commercial products can end up being lemons. This is something [Mike Buss] is familiar with, as he had the misfortune of being stuck using what he declares is the world’s worst USB hub, and it’s not even a mystery discount device from overseas: it’s an HP Thunderbolt Dock G2. It is a sort of combination I/O dock and USB hub, and it caused him no end of frustration until he “fixed” it with a crude workaround.

The problems with [Mike]’s dock come down to two major issues. The first is that the USB-C connection will, if moved even the slightest amount, instantly trigger a disconnect from the host computer. Frankly, that sounds like a defect, but that’s not all. The other issue is that the whole top of the device is actually a giant, hyper-sensitive button. Even a stern gaze seems to be enough to cause it to activate. What does the button do? It puts the host computer to sleep; something that we all agree should suffer from as few false activations as possible.

We’ll spoil the surprise by revealing that the “fix” was nothing more than putting a 3D printed enclosure around the troublesome device, as shown in the image above. Keeping the dock covered and perfectly still at least prevents the two aforementioned issues, and that’s good enough for [Mike].

The curious part of all this is just how badly the device’s design affected normal use. We’d suspect a defect or malfunction, but a cursory search of reviews online suggests [Mike]’s experience isn’t unique. It’s certainly not the first poorly-designed product we’ve seen fixed by a new enclosure, but some problems just aren’t worth the effort of a more elegant solution.

Remote MQTT Temperature Sensor Shows How It’s Done

March 13, 2022 by Donald Papp 7 Comments

First of all, there are definitely simpler ways to monitor remote temperatures, but [Mike]’s remote MQTT temperature sensor and display project is useful in a few ways. Not only does it lay out how to roll such a system from scratch, but it also showcases system features like solar power.

After all, if one simply wants to monitor temperature that’s easily done, but once one wishes to log those temperatures and use them to trigger other things, then rolling one’s own solution starts to get more attractive. That’s where using someone else’s project as a design reference can come in handy.

[Mike’s] solution uses two Wemos D1 boards: one with a DS18B20 temperature sensor for outdoors, and one with a small OLED screen for an interior display. The external sensor relies on a rechargeable 18650 cell and a solar panel for a hassle-free power supply, and the internal sensor (of which there can be many) has a cute enclosure and is powered by USB. On the back end, a Raspberry Pi running an MQTT gateway and Node Red takes care of the operational side of things. The whole system has been happily running for over two years.

What is MQTT? It is essentially a messaging protocol, and takes care of the whole business of reliably communicating data back and forth between IoT devices. It scales very well and doesn’t need to be hard or intimidating; our own [Elliot Williams] can tell you all about implementing it.

ice fishing tent and antenna in a snowy field

Ice Fishing Tent Makes Winter Ham Radio Comfy

March 12, 2022 by Donald Papp 29 Comments

Cross-pollination between different activities and industries can yield some pretty useful techniques or product combinations, and [Steve] shares some details on using ice fishing gear to make winter ham radio activities more comfortable and portable.

With the help of a folding tent shelter, [Steve] was able to create a minimal and self-contained field station that hosted all his needed equipment, and with the help of a small propane heater, stayed quite comfortable during a 24 hour winter event.

For those interested in the radio end of what [Steve] was doing, he goes into detail about the radio equipment and antenna he used, which itself stows easily into a bag and withstood high winds with success. The goal of the event after all was emergency preparedness, and while radio can operate without a wider infrastructure to support it, antenna design is crucial for best results.

As for keeping the operator safe and sound during all this, it turns out that the problem of a pop-up winter shelter that is both light and compact has already been solved by ice fishers; and while it can be fun to roll one’s own solutions, there’s not always a need to re-invent the wheel.

How To Make Laser-cut Decals On The Cheap

March 12, 2022 by Donald Papp 13 Comments

Want to make a sweet adhesive decal with a complex design and floating elements, but all you have is a laser cutter and some tape? Good news, because that’s all you need with this method of creating adhesive tape decals on a laser cutter demonstrated by the folks at [Lasers Over Los Angeles]. The overall technique is very similar to creating vinyl decals and using tape transfer to apply them, but is geared towards laser cutters and nice, cheap tape.

This method also makes applying to non-flat surfaces a breeze.

The way it works is this: paper-based tape (such as blue painter’s tape) is laid down in strips on the laser cutter’s honeycomb bed, forming a nice big rectangle big enough for the intended design. Then, the laser cutter cuts vector art into the tape, resulting in an adhesive decal ready to be stuck to some other surface. Transferring is done by using good quality clear packing tape to “pick up” the decal, then move it to where it needs to be.

To do this, one lays strips of packing tape onto the top of the design on the laser bed, then lifts the design up and away. Move the design to its destination (the clear packing tape helps in eyeballing the final position), press the decal onto the final surface, and carefully peel away the clear packing tape. This works because the packing tape sticks only weakly to the back of the painter’s tape; it’s a strong enough bond to hold the decal, but weak enough that the decal will stick to a surface even better.

It’s true that painter’s tape isn’t as durable as vinyl and the color selection is a bit limited, but design-wise one can go as big as the laser bed allows, and the price is certainly right. Plus it’s easily cut by even the most anemic of diode lasers.

Speaking of desktop vinyl cutters, they may have small working areas compared to most laser cutters, but they have some fantastic workshop applications. They can even do home PCB fabrication, by way of knocking out three essential pieces: the etching mask, solder mask, and solder stencil.

Vintage Meter Repair? It’s Easier With X-Rays

March 6, 2022 by Donald Papp 18 Comments

Here’s an interesting and detailed teardown and repair of a Keithley 2001 7.5 Digit multimeter that is positively dripping with detail. It’s also not every day that we get to see someone using x-ray imaging to evaluate the extent of PCB damage caused by failed electrolytic capacitors.

Dark area is evidence of damage in the multi-layer PCB.

Sadly, this particular model is especially subject to that exact vintage electronics issue: electrolytic capacitor failure and leakage. These failures can lead to destroyed traces, and this particular unit had a number of them (in addition to a few destroyed diodes, just for good measure.) That’s where the x-ray machine comes in handy, because some of the damage is hidden inside the multi-layer PCBs.

[Shahriar], perhaps best known as [The Signal Path], narrates the entire process of fixing up the high-quality benchtop multimeter in a video, embedded below (or you can skip directly to the x-ray machine being broken out.) [Shahriar] was able to repair the device, thanks in part to it being in relatively good shape, and having the right tools available. Older electronics are not always so cooperative; the older a device is, the more likely one is to run into physical and logical standards that no longer exist.

Continue reading “Vintage Meter Repair? It’s Easier With X-Rays” →

How To Solder To Aluminum, Easily

March 6, 2022 by Donald Papp 53 Comments

[Ted Yapo] shared a method of easily and conveniently soldering to aluminum, which depends on a little prep work to end up only slightly more complex than soldering to copper. A typical way to make a reliable electrical connection to aluminum is to use a screw and a wire, but [Ted] shows that it can also be done with the help of an abrasive and mineral oil.

Aluminum doesn’t solder well, and that’s because of the oxide layer that rapidly forms on the surface. [Ted]’s solution is to scour the aluminum with some mineral oil. The goal is to scrape away the oxide layer on the aluminum’s surface, while the mineral oil’s coating action prevents a new oxide layer from immediately re-forming.

After this prep, [Ted] uses a hot soldering iron and a blob of solder, heating it until it sticks. A fair bit of heat is usually needed, because aluminum is a great heat conductor and tends to be lot thicker than a typical copper ground plane. But once the aluminum is successfully tinned, just about anything can be soldered to it in a familiar way.

[Ted] does caution that mineral oil can ignite around 260 °C (500 °F), so a plan should be in place when using this method, just in case the small amount of oil catches fire.

This looks like a simple technique worth remembering, and it seems easier than soldering by chemically depositing copper onto aluminum.

Hardware Hacking 101 Needs Matching Toolkit

March 3, 2022 by Donald Papp 22 Comments

One doesn’t always have the luxury of sipping tea comfortably while hacking a piece of hardware at a fully-equipped workbench, where every tool is within reach. To address this, [Zokol] shares an early look at a hardware hacking toolkit-in-progress, whose purpose is to make hacking sessions as productive as possible while keeping size and weight within reasonable limits. There isn’t a part list yet, but there are some good tips on creating your own.

To put together an effective hardware hacking toolkit, one must carefully consider what kinds of tasks need to be performed, and in what order. Once a basic workflow is identified, one can put together a set of complementary hardware tools and resources to meet the expected needs. The goal is to have the tools to go as far as one can in a single session, and identify any specialized equipment that will be needed later. That way, follow-up sessions can be as effective as possible.

Since hardware hacking is all about inspecting (and possibly modifying the behavior of) electronic devices, [Zokol] observes that step one is always to begin with external interfaces. That means common cables and adapters should all be part of a hardware hacking toolkit, otherwise the session might end awfully early. The next step is to open the device, so common tools and ways to deal with things like adhesives are needed. After that, diagnostic tools like multimeters come into play, with tools becoming more specialized as investigation proceeds. It’s a very sensible way to approach the problem of what to bring (and not bring) in a hardware hacking toolkit, and we can’t wait to see what the final version looks like.

Hardware hacking sometimes involves hardware that can’t be opened without damaging it. The Google Stadia controller is one such piece of hardware, and [Zokol] addressed the problem of how to permanently disable the microphone by figuring out exactly where to drill a hole.