British wartime periscope on a workbench

British Wartime Periscope: A Peek Into The Past

April 22, 2025 by Heidi Ulrich 4 Comments

We all know periscopes serve for observation where there’s no direct line-of-sight, but did you know they can allow you to peer through history? That’s what [msylvain59] documented when he picked up a British military night vision periscope, snagged from a German surplus shop for just 49 euros. Despite its Cold War vintage and questionable condition, the unit begged for a teardown.

The periscope is a 15-kilo beast: industrial metal, cryptic shutter controls, and twin optics that haven’t seen action since flares were fashionable. One photo amplifier tube flickers to greenish life, the other’s deader than a disco ball in 1993. With no documentation, unclear symbols, and adjustment dials from hell, the teardown feels more like deciphering a British MoD fever dream than a Sunday project. And of course, everything’s imperial.

Despite corrosion, mysterious bulbs, and non-functional shutters, [msylvian59] uncovers a fascinating mix of precision engineering and Cold War paranoia. There’s a thrill in tracing light paths through mil-spec lenses (the number of graticules seen that are etched on the optics) and wondering what secrets they once guarded. This relic might not see well anymore, but it sure makes us look deeper. Let us know your thoughts in the comments or share your unusual wartime relics below.

Continue reading “British Wartime Periscope: A Peek Into The Past” →

Hacking A Cheap Rechargeable Lamp With Non-Standard USB-C Connector

April 12, 2025 by Maya Posch 40 Comments

The "USB C" cable that comes with the Inaya Portable Rechargeable Lamp. (Credit: The Stock Pot, YouTube) — The “USB C” cable that comes with the Inaya Portable Rechargeable Lamp. (Credit: The Stock Pot, YouTube)

Recently [Dillan Stock] over at The Stock Pot YouTube channel bought a $17 ‘mushroom’ lamp from his local Kmart that listed ‘USB-C rechargeable’ as one of its features, the only problem being that although this is technically true, there’s a major asterisk. This Inaya-branded lamp namely comes with a USB-C cable with a rather prominent label attached to it that tells you that this lamp requires that specific cable. After trying with a regular USB-C cable, [Dillan] indeed confirmed that the lamp does not charge from a standard USB-C cable. So he did what any reasonable person would do: he bought a second unit and set about to hacking it.

[Dillan] also dug more into what’s so unusual about this cable and the connector inside the lamp. As it turns out, while GND & Vcc are connected as normal, the two data lines (D+, D-) are also connected to Vcc. Presumably on the lamp side this is the expected configuration, while using a regular USB-C cable causes issues. Vice versa, this cable’s configuration may actually be harmful to compliant USB-C devices, though [Dillan] did not try this.

With the second unit in hand, he then started hacking it, with the full plans and schematic available on his website.

The changes include a regular USB-C port for charging, an ESP32 board with integrated battery charger for the 18650 Li-ion cell of the lamp, and an N-channel MOSFET to switch the power to the lamp’s LED. With all of the raw power from the ESP32 available, the two lamps got integrated into the Home Assistant network which enables features such as turning the lamps on when the alarm goes off in the morning. All of this took about $7 in parts and a few hours of work.

Although we can commend [Dillan] on this creative hack rather than returning the item, it’s worrying that apparently there’s now a flood of ‘USB C-powered’ devices out there that come with non-compliant cables that are somehow worse than ‘power-only’ USB cables. It brings back fond memories of hunting down proprietary charging cables, which was the issue that USB power was supposed to fix.

Continue reading “Hacking A Cheap Rechargeable Lamp With Non-Standard USB-C Connector” →

The Lowly Wall Wart Laid Bare

April 2, 2025 by Tom Nardi 18 Comments

Getting a look at the internals of a garden variety “wall wart” isn’t the sort of thing that’s likely to excite the average Hackaday reader. You’ve probably cracked one open yourself, and even if you haven’t, you’ve likely got a pretty good idea of what’s inside that sealed up brick of plastic. But sometimes a teardown can be just as much about the journey as it is the end result.

Truth be told, we’re not 100% sure if this teardown from [Brian Dipert] over at EDN was meant as an April Fool’s joke or not. Certainly it was posted on the right day, but the style is close enough to some of his previous work that it’s hard to say. In any event, he’s created a visual feast — never in history has an AC/DC adapter been photographed so completely and tastefully.

[Brian] even goes so far as to include images of the 2.5 lb sledgehammer and paint scraper that he uses to brutally break open the ultrasonic-welded enclosure. The dichotomy between the thoughtful imagery and the savage way [Brian] breaks the device open only adds to the surreal nature of the piece. Truly, the whole thing seems like it should be part of some avant garde installation in SoHo.

After he’s presented more than 20 images of the exterior of the broken wall wart, [Brian] finally gets to looking at the internals. There’s really not much to look at, there’s a few circuit diagrams and an explanation of the theory behind these unregulated power supplies, and then the write-up comes to a close as abruptly as it started.

So does it raise the simple teardown to an art form? We’re not sure, but we know that we’ll never look at a power adapter in quite the same way again.

Tiny Bubbles In The Memory

March 31, 2025 by Al Williams 15 Comments

We are always fascinated by bubble memory. In the late 1970s, this was the “Next Big Thing” that, as you may have guessed, was, in fact, not the next big thing at all. But there were a number of products that used it as non-volatile memory at a time when the alternative was tape or disk. [Smbakeryt] has a cool word processor with an acoustic coupler modem made by Teleram. Inside is — you guessed it — bubble memory.

The keyboard was nonfunctional, but fixable. Although we wouldn’t have guessed the problem. Bubble memory was quite high tech. It used magnetic domains circulating on a thin film of magnetic material. Under the influence of a driving field, the bubbles would march past a read-write head that could create, destroy, or read the state of the bubble.

Why didn’t it succeed? Well, hard drives got cheap and fairly rugged. The technology couldn’t compete with the high-density hard drives that could be reached with improved heads and recording strategies. Bubble memory did find use in high-vibration items, but also wound up in things like this terminal, at least one oscilloscope, and a video game.

Bubble memory evolved from twistor memory, one of several pre-disk technologies. While they are hard to come by today, you can find the occasional project that either uses some surplus or steals a part off of a device like this one.

Continue reading “Tiny Bubbles In The Memory” →

Inside A Fake WiFi Repeater

March 27, 2025 by Maya Posch 29 Comments

Fake WiFi repeater with a cheap real one behind it. (Credit: Big Clive, YouTube)

Over the years we have seen a lot of fake electronics, ranging from fake power saving devices that you plug into an outlet, to fake car ECU optimizers that you stick into the OBD port. These are all similar in that they fake functionality while happily lighting up a LED or two to indicate that they’re doing ‘something’. Less expected here was that we’d be seeing fake WiFi repeaters, but recently [Big Clive] got his hands on one and undertook the arduous task of reverse-engineering it.

The simple cardboard box which it comes in claims that it’s a 2.4 GHz unit that operates at 300 Mbps, which would be quite expected for the price. [Clive] obtained a real working WiFi repeater previously that did boast similar specifications and did indeed work. The dead giveaway that it is a fake are the clearly fake antennae, along with the fact that once you plug it in, no new WiFi network pops up or anything else.

Inside the case – which looks very similar to the genuine repeater – there is just a small PCB attached to the USB connector. On the PCB are a 20 Ohm resistor and a blue LED, which means that the LED is being completely overdriven as well and is likely to die quite rapidly. Considering that a WiFi repeater is supposed to require a setup procedure, it’s possible that these fake repeaters target an audience which does not quite understand what these devices are supposed to do, but they can also catch more informed buyers unaware who thought they were buying some of the cheap real ones. Caveat emptor, indeed.

Continue reading “Inside A Fake WiFi Repeater” →

Why Are Micro Center Flash Drives So Slow?

March 26, 2025 by Maya Posch 45 Comments

Every year, USB flash drives get cheaper and hold more data. Unfortunately, they don’t always get faster. The reality is, many USB 3.0 flash drives aren’t noticeably faster than their USB 2.0 cousins, as [Chase Fournier] found with the ultra-cheap specimens purchased over at his local Micro Center store.

Although these all have USB 3.0 interfaces, they transfer at less than 30 MB/s, but why exactly? After popping open a few of these drives the answer appears to be that they use the old-style Phison controller (PS2251-09-V) and NAND flash packages that you’d expect to find in a USB 2.0 drive.

Across the 32, 64, and 256 GB variants the same Phison controller is used, but the PCB has provisions for both twin TSOP packages or one BGA package. The latter package turned out to be identical to those found in the iPhone 8. Also interesting was that the two 256 GB drives [Chase] bought had different Phison chips, as in one being BGA and the other QFP. Meanwhile some flash drives use eMMC chips, which are significantly faster, as demonstrated in the video.

It would seem that you really do get what you pay for, with $3 “USB 3.0” flash drives providing the advertised storage, but you really need to budget in the extra time that you’ll be waiting for transfers.

Continue reading “Why Are Micro Center Flash Drives So Slow?” →

Teardown Of Casio Credit Card-Sized Radio

March 26, 2025 by Maya Posch 33 Comments

These days we don’t get too fussed about miniaturized electronics, not when you can put an entire processor and analog circuitry on a chip the size of a grain of sand. Things were quite different back in the 1980s, with the idea of a credit card-sized radio almost preposterous. This didn’t stop the engineers over at Casio from having a go at this and many other nutty ideas, with [Matt] from Techmoan having a go at taking one of these miniaturized marvels apart.

The Casio FM Stereo radio in happier days. (Credit: Techmoan, YouTube)

On the chopping block is the FM stereo device that was featured in a previous episode. Out of the four credit card-sized radios in that video, the one with the rechargeable battery (obviously) had ceased to work, so it was the obvious choice for a teardown. This mostly meant peeling off the glued-on top and bottom, after which the circuitry became visible.

In addition to the battery with a heavily corroded contact, the thin PCB contains a grand total of three ICs in addition to the analog circuitry. These were identified by [Spritetm] as an AM/FM tuner system IC (TA7792), an FM PLL MPX (TA7766AF) and a headphone amplifier (TA7767F), all of them manufactured by Toshiba.

Although [Matt] reckons this was a destructive teardown, we’re looking forward to the repair video where a fresh cell is soldered in and the case glued back together. Continue reading “Teardown Of Casio Credit Card-Sized Radio” →