Spy Tech: A Quiet Radio For Spies

May 20, 2026 by Al Williams 9 Comments

Normally, when you think of a radio transmitter, you want the strongest signal and range. But if your radio operator is secretly operating as a spy, broadcasting their position isn’t a feature; it is a liability. This fact didn’t escape World War II radio designers.

In late 1942, the British realized they needed a way for Special Operation Executive agents, resistance members, and other friendly forces to communicate with an aircraft without attracting undue attention. Two engineers from the Royal Corps of Signals developed a pair of transceivers — the S-Phone — operating around 380 MHz just for this purpose. Frequencies this high were unusual at the time, which further deterred enemy detection.

The output power was below 200 mW, and the ground equipment consisted of a dipole strapped to the operator. No transistors, so with rechargable batteries, the rig weighed about fifteen pounds and reused some parts of a paratrooper radio, Wireless Set Number 37. The other side of the connection was installed in an airplane.

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Between-Device Sharing Still Sucks

May 20, 2026 by Zoe Skyforest 95 Comments

Once upon a time, computing was simple. You had files on a floppy disk. If you wanted to take them to a different computer, you ejected the disk from one machine and put it in another. It wasn’t fast, but it was easy and intuitive. Besides, you probably only had one computer of your own, anyway.

Life has since gotten a lot more complex. You’ve got a desktop, a laptop, a work laptop, your personal and business phones, and a smart watch to boot. You live amongst a swirling maelstrom of terabytes of data. Despite all the technical advances that got you here, it’s still a pain to get a file from one device to another, even when they’re sitting on the same desk. Why?!

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How Pulse Oximetry Figures Out Your Blood Oxygen Levels

May 19, 2026 by Zoe Skyforest 13 Comments

If you’ve ever had a medical team investigating cardiac issues, you’ve probably had a bunch of electrodes stuck all over your chest and been hooked up to an electrocardiogram. This is the gold standard when it comes to understanding electrical activity in the heart and can diagnose a great many conditions. However, sometimes doctors just need the basic information—your pulse rate, and whether or not there’s actually any oxygen in your blood.

Thankfully, there’s a cheap and simple device that can offer that exact information. It’s the pulse oximeter, and it’s a key piece of equipment that’s just about vital for monitoring vitals. Let’s learn how it works!

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How Search Engines Enabled Finding Needles In A WWW-Sized Haystack

May 19, 2026 by Maya Posch 13 Comments

When the World Wide Web surged into existence during the 1990s, we were introduced to the problem of how to actually find something in this ever-ballooning construction zone that easily outpaced even the fastest post-WW2 urban sprawl. Although domain names provided a way to find servers using DNS rather than having to mash in IP addresses, you still somehow had to know the relevant URL.

A range of solutions were thought up over time, ranging from printed Yellow Pages type guides, to online curated lists of resources, as well as things like web rings where one website would link to a relevant similar website. This was the time when word-of-mouth was also very relevant, with people proudly announcing their own website on Geocities or other hosting service.

Search engines already existed long before the WWW became the hot new thing during the 1990s, but it was the WWW that would really push them to their limits. As anyone who used search engines for the WWW can attest, they had many issues. Often you’d end up using multiple search engines to find something, and despite fierce competition between web search engines to become the starting page for their browser, actually finding things on the WWW remained a tough problem.

Since a web search engine ‘just’ has to index the WWW and match a search query against the results, why was this such a hard problem that persisted until Google apparently cracked the code?

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How To Make Steel That Breathes

May 18, 2026 by Zoe Skyforest 15 Comments

There are plenty of porous materials out there that we’re all readily familiar with. Fabrics and wood are great examples, allowing liquids or gases to pass through to a certain degree—a property which is useful or problematic depending on the application.

Metals, however, are not something we would readily consider to be porous. They are solid, unyielding, and impermeable. However, with the right techniques, it is possible to produce so-called “breathable” steel, which has particularly interesting applications in the molding industry.

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This Week In Security: Android Exposes ADB, ShinyHunters Get Paid, Robot Dogs, And More

May 18, 2026 by Mike Kershaw 26 Comments

Google has patched an Android ADB bug in the May security patch set. If you have a Pixel phone you should already have the patches, and most other major manufacturers should be close behind. Unfortunately, the biggest risk from this patch will be to the vendors who are also the least likely to release timely – or any – security updates.

ADB, the Android Debug Bridge, is the main tool for installing apps during development and debugging apps while they’re running. It can also be used to side-load apps from a PC. While most normal users are unlikely to ever enable it, developers typically do and some power users might when jailbreaking a device or setting parameters not exposed in the Android UI. Debugging can be done locally via USB, or optionally over the network. To protect the device, the user must unlock the Android device and authorize each new debug agent.

Covered by Risky.Biz, a bug introduced in 2020, and present in every Android release since, allowed bypassing authorization entirely if network debugging was enabled and at least one connection had been made to the ADB service in the past. This happens because ADB compares the certificate of the incoming debug connection with the list of saved certificates. If the certificate type does not match — for instance supplying an Ed25519 certificate instead of a RSA certificate — ADB has been incorrectly handling the error code, and allowing the connection.

In most programming languages, false is considered zero, and true is considered anything not zero. The certificate API returns a 1 for a valid match, a zero for an invalid match, and a negative-one for a type mismatch. Negative one is not zero, so when treated as a boolean value, it becomes true.

To exploit the bug, ADB must be enabled in wireless mode, and there must be at least one trusted device in the ADB configuration. For the average user this is an unlikely combination, but for developers, the time to update is now.

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Teardown: ChargeTab Emergency Phone Charger

May 14, 2026 by Tom Nardi 55 Comments

If you own a modern smartphone, there’s an excellent chance that its battery has run dangerously low on you at least a few times. Murphy’s Law dictates that this will naturally occur at the worst possible moment, say when you need to make an important phone call or when you’re lost and need to navigate home.

With this in mind, it’s not hard to see how a product like the ChargeTab would have a certain appeal. A small $10 USD device that you can keep in the car or pack in a bag that’s always available to charge your phone in an emergency.

Because it’s not meant to be used regularly — indeed it may never get used at all — it’s not completely unreasonable that such a device would only be good for one or two charges before its spent and must be replaced. It’s a bit like keeping a road flare in the car; it’s unlikely you’ll ever use the thing, but if you do, it only needs to work once.

But then what? According to ChargeTab, once the gadget has depleted its internal ~3,000 mAh battery it cannot be recharged and is no longer usable. Now to be fair, they specifically tell you to not throw it in the trash. They’ll send you a free return label to ship it back to them, at which point it will be refurbished and put back into circulation. The company argues that this recycling program, combined with the fact that the batteries inside the ChargeTabs were supposedly diverted from landfills in the first place, makes their entire operation eco-friendly.

Yet here we have a pair of ChargeTabs that were thrown in the regular garbage and would have taken a one-way trip to the local landfill if it wasn’t for the fact that I habitually dig through garbage cans like a raccoon. So let’s take a look at what’s inside one of these emergency phone chargers and if the idea is as green as the company claims.

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