Helping Hands, Reinvented

January 8, 2021 by Kristina Panos 9 Comments

[Nixie] was tired of using whatever happens to be around to hold things in place while soldering and testing. It was high time to obtain a helping hands of some kind, but [Nixie] was dismayed by commercial offerings — the plain old alligator clips and cast metal type leave a lot to be desired, and the cooling tube cephalopod type usually have the alligator clips just jammed into the standard tube ends with no thought given to fine control or the possibility of reducing cable count.

[Nixie] happened to have some unneeded cooling tube lying around and started designing a new type of helping hands from the ground plane up. Taking advantage of the fact that cooling tubes are hollow, [Nixie] routed silicone-jacketed wires through them for power and low speed signals. These are soldered to five banana jacks that are evenly spaced around an alligator clip.

Even if you don’t need power, all those extra alligators would come in quite handy for circuit sculpture or anything else that requires a lot of hands. [Nixie] put the files up on Thingiverse if you want to make your own.

We’ve seen plenty of helping hands over the years, but this concrete-based helper ought to cement your decision to make your own.

Remoticon Video: Basics Of RF Emissions Debugging Workshop

January 8, 2021 by Mike Szczys 5 Comments

These days we’re surrounded by high-speed electronics and it’s no small feat that they can all play nicely in near proximity to each other. We have RF emissions standards to thank, which ensure new products don’t spew forth errant signals that would interfere with the data signals traveling through the ether. It’s long been the stuff of uber-expensive emissions testing labs, and failure to pass can leave you scratching your head. But as Alex Whittimore shows in this workshop from the 2020 Hackaday Remoticon, you can do a lot of RF emissions debugging with simple and inexpensive tools.

Professionally-made probes in several sizes

You can get a surprisingly clear picture of what kind of RF might be coming off of a product by probing it on your own workbench. Considering the cost of the labs performing FCC and other certifications, this is a necessary skill for anyone who is designing a product headed to market — and still damn interesting for everyone else. Here you can see two examples of the probes used in the process. Although one is a pack of professional tools and other is a bit of enameled wire (magnet wire), both are essentially the same: a loop of wire on which a magnetic field will induce a very small current. Add a Low-Noise Amplifier (LNA) and you’ll be up and measuring in no-time.

I really enjoyed how Alex started his demo with “The Right Way^TM” of doing things — using a proper spectrum analyzer to visualize data from the probes. But the real interesting part is “The Hacker Way^TM” which leverages an RTL-SDR dongle and some open-source software to get the same job done. Primarily that means using SDRAngel and QSpectrumAnalyzer which are both included in the DragonOS_LTS which can be run inside of a virtual machine.
Continue reading “Remoticon Video: Basics Of RF Emissions Debugging Workshop” →

Bad Idea For Desoldering Actually Might Be Pretty Smart

January 6, 2021 by Dan Maloney 49 Comments

This video on building a DIY desoldering iron says it all right up front: this is stupid and dangerous, and you shouldn’t do it. But that doesn’t mean it doesn’t work, or that it doesn’t have potential to be turned into something else.

The story begins, as it often does these days, on the pages of Amazon as [AnotherMaker] shopped for a real desoldering setup. Despite a case of sticker shock, he took the plunge on a nice Hakko vacuum desolderer, but as is also often the case, it failed to arrive. Rather than accept defeat, [AnotherMaker] purchased a cheap-o soldering iron and a brass tee fitting for small-bore tubing that would chuck nicely into the spot where the stock tip once lived, giving him a way to both melt solder and move air.

Unfortunately, rather than applying a vacuum, he chose to blast 100 PSI compressed air through the tip, which certainly moves a lot of solder, perhaps at the cost of burns and eye injuries. The potential for accidental short circuits is pretty high too, but c’mon — it’s not like we all haven’t flicked or dropped a board to desolder something. Is this really much different?

As fraught with peril as this method may be, [AnotherMaker] is onto something here. Perhaps adding a 3D-printed venturi generator could turn that blast of air into a vacuum. Or maybe a vacuum pump for a manual pick-and-place would do the trick too.

Continue reading “Bad Idea For Desoldering Actually Might Be Pretty Smart” →

Review: Pine64 Pinecil Soldering Iron

January 5, 2021 by Jenny List 98 Comments

There was a time when decent quality soldering irons were substantial affairs, soldering stations with a chunky base unit containing the electronics and a lightweight handheld iron for the work. That has changed with the arrival of a new breed of microprocessor controlled lightweight handheld irons. There’s a new kid on the block from a company we associate more with open-source phones, laptops, and single board computers, Pine64 have produced the Pinecil. It’s a lightweight handheld iron with some innovative features at an attractive price, but does it raise the bar sufficiently to take on the competition?

I put the Pinecil through its paces, and and although the device is fully open source, give it a teardown for good measure. Spoiler: it’s my new favorite.
Continue reading “Review: Pine64 Pinecil Soldering Iron” →

Simple AC Current Detector Built On A 9 Volt

January 4, 2021 by Lewin Day 59 Comments

When working around mains voltages, it can be useful to know whether a given circuit is live or not. While this can be done by direct connection with a multimeter, non-contact methods are available too. A great example is this simple wireless AC current detector from [NEW PEW].

The circuit is a simple one, and a classic. The spring from a ballpoint pen is soldered to the base of a BC547 transistor, and when held close enough to a conductor carrying AC power, a current is induced in the spring which is sufficient to turn the transistor on. The transistor then switches on a second BC547, which lights an LED. The whole circuit is built on top of a battery clip so it can be run straight from the top of a standard 9 volt battery.

It’s a circuit you’ll find all over the place, even built into many modern multimeters. It can be particularly useful to help avoid drilling through mains wires embedded in the walls of your home. Of course, if you’d like even more information about what’s lurking within your walls, consider this capacitive imaging hack. Video after the break.

Continue reading “Simple AC Current Detector Built On A 9 Volt” →

Unbricking A SEGGER J-Link V9 Debug Probe

December 30, 2020 by Maya Posch 23 Comments

Last year [Emil] found themselves in the situation where a SEGGER J-link debug probe suddenly just stopped working. This was awkward not only because in-circuit debuggers are vital pieces of equipment in embedded firmware development, but also because they’re not that cheap. This led [Emil] to take the device apart to figure out what was wrong with it.

After checking voltages on the PCB, nothing obvious seemed wrong. The Tag-Connect style JTAG header on the PCB appeared to be a good second stop, requiring only a bit of work to reverse-engineer the exact pinout and hook up an ST-Link V2 in-circuit debugger to talk with the STM32F205RC MCU on the PCB. This led to the interesting discovery that apparently the MCU’s Flash ROM had seemingly lost the firmware data.

Fortunately [Emil] was able to flash back a version of the firmware which was available on the internet, allowing the J-Link device to work again. This was not the end of the story, however, as after this the SEGGER software was unable to update the firmware on the device, due to a missing bootloader that was not part of the firmware image.

Digging further into this, [Emil] found out a whole host of fascinating details about not only these SEGGER J-Link devices, but also the many clones that are out there, as well as the interesting ways that SEGGER makes people buy new versions of their debug probes.

(Thanks Zelea for the tip)

Magnetic Motorized Plasma Cutter Track

December 29, 2020 by Danie Conradie 10 Comments

Affordable plasma cutters are becoming a popular step up from an angle grinder for cutting sheet metal in the home workshop, but cutting long straight lines can be laborious and less than accurate. [Workshop From Scratch] was faced with this problem, so he built a motorized magnetic track for his plasma cutter.

Thanks to a pair of repurposed electromagnetic door looks and adjustable base width, the track can be mounted on any piece of magnetic steel. The track itself consists of a pair of linear rods, with the torch mounts sliding along on linear bearings. A lead screw sits between the two linear rods, and is powered by an old cordless drill with the handle cut off. Its trigger switch was replaced by a speed controller and two-way switch for direction control, and a power supply took the place of the battery. The mounting bracket for the plasma torch is adjustable, allowing the edge of the steel to be cut at an angle if required.

While limit switches on the end of the track might be a preferable option to prevent sliding base to hit the ends of the tracks, the clutch in the electric drill should be good enough to prevent damage if the operator is distracted.

[Workshop From Scratch] is really living up to the name of his YouTube channel, having built many of the other tools used in the video himself. Just a few examples are the XY-table, hydraulic adjustable workbench and hydraulic shop crane. Continue reading “Magnetic Motorized Plasma Cutter Track” →