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Sniffing Around Inside a ThinkPad Battery

For most people, a battery pack that’s misbehaving simply means it’s time to get a new battery. But when the battery in their ThinkPad wasn’t able to muster up more than 20 minutes of runtime, [Shrinath Nimare] saw an opportunity to dig deeper and do a bit of investigating.

The problem seemed to be that the battery pack was reporting that it was 100% charged at just 11.7 V instead of the correct 12.3 V. As it turns out, that 11.7 V figure is only slightly above what the battery should be when its run flat — so in reality, the battery was never actually getting a charge and would report that it was dead after just a few minutes of use. But why?

With a logic analyzer attached to the pins of the battery, [Shrinath] set out to sniff its communications with the ThinkPad.  Even if it wouldn’t lead to fixing the battery pack, the information obtained would potentially be useful for other projects, such as creating a custom high-capacity LiFePO4 pack down the line.

With the pack opened, [Shrinath] determined that a 51F51 BMS IC was running the show. The battery communicates with the host computer over SMBus, which is very similar to I2C. In fact, they’re so similar that [Shrinath] was able to use the I2C decoder in sigrok to break out the read and write commands and compare them to a PDF of the Smart Battery Data Specification.

Using the I2C decoder to read SMBus messages.

With a few captures in hand, [Shrinath] made some good progress in decoding what the two devices are saying to each other. For example, when the computer sent the command 0x15, the battery correctly responded with the desired charge voltage of 12.3 V. The command 0x18 was then given, which the specification says should cause the battery to report its capacity. Here again, valid data was returned, confirming that [Shrinath] was on the right path.

Even though it’s still early in the investigation, [Shrinath] had enough trouble finding practical examples of sniffing SMBus data that they thought it would be worth uploading their captures and notes to Hackaday.io. Hopefully further poking will show if the battery can be revived, but even if not, we’re always glad to see when hackers are willing to document their exploits for the benefit of the community.

This actually isn’t the first time we’ve heard of somebody snooping on their ThinkPad battery — back in 2020, we covered [Alexander Parent]’s efforts to create an open source battery pack for the T420 based on the ATtiny85.

Fluke Meter Fails with a Simple Problem

[TheHWcave] found a Fluke 27 multimeter that looked like it had had quite a rough life. At first, the display flashed an overload indicator until he gave it a good smack—or, as he likes to call it, percussive maintenance. Even then, it would not give good readings, so it was time to open it up.

The display did work, so the obvious theory was something wrong with the analog board. Removing the shields showed what looked like a normal enough PCB. Or at least, the components looked fine. But on the solder side of the board, there was some corrosion on two contacts, so some careful cleaning and resoldering fixed the meter to be as good as new on at least some scales.

Tracing the pins, the corrosion put a resistor between two pins of an op-amp. The only remaining problem was the milliamp scale, but that was a simple blown fuse in the line. Since it was working, it was worth some time to clean up the ugly exterior, which is only cosmetic but still worth a little effort. He left the plastic case cracked and beaten, but he put a lot of effort into clearing up the display window.

You might wonder why you’d fix a meter when you can get one so cheap. However, these name-brand meters are high-quality and new, quite expensive. Even older ones can be worth the effort. While you usually don’t need an X-ray machine to fix something like this, it can’t hurt.

Fail of the Week: The SMD Crystal Radio That Wasn’t

The crystal radio is a time-honored build that sadly doesn’t get much traction anymore. Once a rite of passage for electronics hobbyists, the classic coil-on-an-oatmeal-carton and cat’s whisker design just isn’t that easy to pull off anymore, mainly because the BOM isn’t really something that you can just whistle up from DigiKey or Mouser.

Or is it? To push the crystal radio into the future a bit, [tsbrownie] tried to design a receiver around standard surface-mount inductors, and spoiler alert — it didn’t go so well. His starting point was a design using a hand-wound air-core coil, a germanium diode for a detector, and a variable capacitor that was probably scrapped from an old radio. The coil had three sections, so [tsbrownie] first estimated the inductance of each section and sourced some surface-mount inductors that were as close as possible to their values. This required putting standard value inductors in series and soldering taps into the correct places, but at best the SMD coil was only an approximation of the original air-core coil. Plugging the replacement coil into the crystal radio circuit was unsatisfying, to say the least. Only one AM station was heard, and then only barely. A few tweaks to the SMD coil improved the sensitivity of the receiver a bit, but still only brought in one very local station.

[tsbrownie] chalked up the failure to the lower efficiency of SMD inductors, but we’re not so sure about that. If memory serves, the windings in an SMD inductor are usually wrapped around a core that sits perpendicular to the PCB. If that’s true, then perhaps stacking the inductors rather than connecting them end-to-end would have worked better. We’d try that now if only we had one of those nice old variable caps. Still, hats off to [tsbrownie] for at least giving it a go.

Note: Right after we wrote this, a follow-up video popped up in our feed where [tsbrownie] tried exactly the modification we suggested, and it certainly improves performance, but in a weird way. The video is included below if you want to see the details.

A Month Without IPV4 is Like a Month Without…

Recently, there was a Mastodon post from [nixCraft] challenging people to drop their NAT routers for the month of November and use only IPv6. What would it be like to experience “No NAT November?” [Alex Haydock] decided to find out.

What did he learn? You’d imagine he’d either wholeheartedly embrace IPv6 or stagger back in and warn everyone not to mess with their configuration. Instead, he recommends you go IPv6 mostly. He notes he is only talking about a home network, not necessarily networks for a big company or an Internet carrier. That’s a different topic.

IPv6 has been around since 1998, but it has been slow to catch on. However, OS support seems universal at this point. [Alex] was able to easily switch on IPv6 only using Windows, macOS, and several Linux flavors. He didn’t use any Android devices, but they should be OK. His iOS phones were fine.

Where he did have problems was with embedded devices like the Nintendo Switch and a Steam Deck — surprising, since the Steam Deck uses Linux. Actually, the Steam device does support IPV6, it just thinks that if it doesn’t have an IPv4 network, the network must be down.

Some home networking gear also required IPv4 addresses to use their management interfaces. That’s especially funny since the devices clearly know about IPv6. They just don’t serve web pages over their IPv6 address.

Unfortunately, there are many websites that do not have IPV6 servers. That’s not as rare as you might think and [Alex] points out offenders like GitHub, Reddit, Discord, and Steam. No IPv4, no access to those and many other sites.

So despite being No NAT November, it was necessary to set up a NAT64 gateway to read IPv4-only websites. However, unlike normal IPv4 NAT (NAT44), you can use a NAT64 gateway anywhere on the network. [Alex’s] ISP hosts a NAT64 and DNS64 instance and that solved his problem.

The post goes on about other specific cases — if you’ve ever even thought about IPv6, it is worth a read. Switching over? Probably not yet, but as [Alex] points out, with a little work and perseverance, it is possible.

In addition to our earlier coverage of why IPv6 isn’t more popular, we’ve also made the arguments about why it should be.

3D Printing Threaded Replacements

Printing an object with threads is nothing new. If you know the specifications on the other thread or you are in control of it, no problem. But [Shop Therapy] wanted to print parts that mate with an existing unknown thread. Out come the calipers.

The first measurement is the height. He rounded that up in the video but mentioned in the comments that it should really be a little smaller so that it seats properly.

After that, he measures the pitch and the major diameter. Next, of course, is the minor diameter. The pitch is related to the spacing of the threads, the major diameter is the diameter of the outside part of the threads, and the minor diameter is the neck without threads.

Next, he’s off to Fusion 360 to design the matching cap. Of course, you could use whatever 3D CAD software you like. Fusion does have some nice thread-related operations, and while it isn’t exactly free, you can get licenses for personal use with no difficulty.

Printing threads has its ups and downs. We prefer embedding metal threads into our prints.

Car Radio Chip Goes Into DIY Build

[Sjef Verhoeven] still loves radio and enjoys the challenge of listening to radio signals from far away. He wanted to build his own radio and turned to the TEF6686 chip, a device often found in car radios. It is known to be very sensitive and seemed perfect for pulling in weak signals. So [Sjef] built this DIY radio and shares the details in this recent Spectrum post.

Unlike older radio-on-chip devices, the TEF6686 is a DSP, which, according to the post, is part of the reason it is ultrasensitive. Even though it is made for car radios, the device is versatile and can pick up shortwave as well as the usual broadcast bands, with the right configuration.

Initially, [Sjef] wanted to design his own tuner but rapidly found inexpensive modules. These had shielding and through-hole pins, making it much easier to deploy a radio using the chip. The modules run around $25 or less.

The rest of the project centers around an ESP32 and an OLED display, along with switches and encoders. The device requires a host to upload its firmware, so a device with a lot of flash memory was a must. The host must also store fonts for the OLED, and [Sjef] even included a database of ham radio callsigns so that when receiving a North American station, you can instantly see which state or province the station is probably in.

If you want to build a duplicate of this radio, all the details are on GitHub. You can also find kit versions.

If you want to build your own shortwave radio, you could spend more. Or, break out a breadboard, if you prefer.

Chess What: One More Pi-Powered Board

PI Board chess board on a table in a room

Chess is timeless, but automating it? That’s where the real magic begins. Enter [Tamerlan Goglichidze]’s Pi Board, an automated chess system that blends modern tech with age-old strategy. Inspired by Harry Potter’s moving chessboard and the commercial Square Off board, [Tamerlan] re-imagines the concept using a Raspberry Pi, stepper motors, and some clever engineering. It’s not just about moving pieces — it’s about doing so with precision and flair.

At its core, the Pi Board employs an XY stepper motor grid coupled with magnets to glide chess pieces across the board. While electromagnets seemed like a promising start, [Tamerlan] found them impractical due to overheating and polarity-switching issues. Enter servo linear actuators: efficient, precise, and perfect for the job.

But the innovation doesn’t stop there. A custom algorithm maps the 8×8 chess grid, allowing motors to track positions dynamically—no tedious resets required. Knight movements and castling? Handled with creative coding that keeps gameplay seamless. [Tamerlan] explains it all in his sleekly designed build log.

Though it hasn’t been long since we featured a Pi-powered LED chess board, we feel that [Tamerlan]’s build stands out for its ingenuity and optimization. For those still curious, we have a treasure trove of over fifty chess-themed articles from the last decade. So snuggle up during these cold winter months and read up on these evergreens!

OSHW Battery Tester Aims to Help Tame Lithium Cells

It’s no exaggeration to say that the development of cheap rechargeable lithium-ion batteries has changed the world. Enabling everything from smartphones to electric cars, their ability to pack an incredible amount of energy into a lightweight package has been absolutely transformative over the last several decades. But like all technologies, there are downsides to consider — specifically, the need for careful monitoring during charging and discharging.

As hardware hackers, we naturally want to harness this technology for our own purposes. But many are uncomfortable about dealing with these high-powered batteries, especially when they’ve been salvaged or come from some otherwise questionable origin. Which is precisely what the Smart Multipurpose Battery Tester from [Open Green Energy] is hoping to address.

Based on community feedback, this latest version of the tester focuses primarily on the convenient 18650 cell — these are easily sourced from old battery packs, and the first step in reusing them in your own projects is determining how much life they still have left. By charging the battery up to the target voltage and then discharging it down to safe minimum, the tester is able to calculate its capacity.

It can also measure the cell’s internal resistance (IR), which can be a useful metric to compare cell health. Generally speaking, the lower the IR, the better condition the battery is likely to be in. That said, there’s really no magic number you’re looking for — a cell with a high IR could still do useful work in a less demanding application, such as powering a remote sensor.

If you’re not using 18650s, don’t worry. There’s a JST connector on the side of the device where you can connect other types of cells, such as the common “pouch” style batteries.

The open source hardware (OSHW) device is controlled by the Seeed Studio XIAO ESP32S3, which has been combined with the LP4060 charger IC and a AP6685 for battery protection. The user interface is implemented on the common 0.96 inch 128X64 OLED, with three buttons for navigation. The documentation and circuit schematics are particularly nice, and even if you’re not looking to build one of these testers yourself, there’s a good chance you could lift the circuit for a particular sub-system for your own purposes.

Of course, testing and charging these cells is only part of the solution. If you want to safely use lithium-ion batteries in your own home-built devices, there’s a few things you’ll need to learn about. Luckily, [Arya Voronova] has been working on a series of posts that covers how hackers can put this incredible technology to work.

Torque Testing 3D Printed Screws

Unless you’ve got a shop with a well-stocked hardware bin, it’s a trip to the hardware store when you need a special screw. But [Sanford Prime] has a different approach: he prints his hardware, at least for non-critical applications. Just how much abuse these plastic screws can withstand was an open question, though, until he did a little torque testing to find out.

To run the experiments, [Sanford]’s first stop was Harbor Freight, where he procured their cheapest digital torque adapter. The test fixture was similarly expedient — just a piece of wood with a hole drilled in it and a wrench holding a nut. The screws were FDM printed in PLA, ten in total, each identical in diameter, length, and thread pitch, but with differing wall thicknesses and gyroid infill percentages. Each was threaded into the captive nut and torqued with a 3/8″ ratchet wrench, with indicated torque at fastener failure recorded.

Perhaps unsurprisingly, overall strength was pretty low, amounting to only 11 inch-pounds (1.24 Nm) at the low end. The thicker the walls and the greater the infill percentage, the stronger the screws tended to be. The failures were almost universally in the threaded part of the fastener, with the exception being at the junction between the head and the shank of one screw. Since the screws were all printed vertically with their heads down on the print bed, all the failures were along the plane of printing. This prompted a separate test with a screw printed horizontally, which survived to a relatively whopping 145 in-lb, which is twice what the best of the other test group could manage.

[Sanford Prime] is careful to note that this is a rough experiment, and the results need to be taken with a large pinch of salt. There are plenty of sources of variability, not least of which is the fact that most of the measured torques were below the specified lower calibrated range for the torque tester used. Still, it’s a useful demonstration of the capabilities of 3D-printed threaded fasteners, and their limitations.

From Cans To Sheet Metal, With Ease

Aluminium drinks cans make a great source of thin sheet metal which can be used for all manner of interesting projects, but it’s safe to say that retrieving a sheet of metal from a can is a hazardous process. Cut fingers and jagged edges are never far away, so [Kevin Cheung]’s work in making an easy can cutter is definitely worth a look.

Taking inspiration from a rotary can opener, he uses a pair of circular blades in an adjustable injection moulded plastic frame. If you’ve used a pipe cutter than maybe you are familiar with the technique, as the blade rotates round the can a few times it slowly scores and cuts through the metal. Doing the job at both ends of the can reveals a tube, which cna be then cut with scissors and flattened to make a rectangular metal sheet. Those edges are probably sharp, but nothing like the jagged finger-cutters you’d get doing the same by hand. The full video can be seen below the break, and the files to 3D print the plastic parts of the cutter can be found at the bottom of a page describing the use of cans to make a shingle roof.

Modular Breadboard Snaps You Into Benchtop Tidiness

Solderless breadboards are a fantastic tool for stirring the creative juices. In a few seconds, you can go from idea to prototype without ever touching the soldering iron. Unfortunately, the downside to this is that projects tend to expand to occupy all the available space on the breadboard, and the bench surrounding the project universally ends up cluttered with power supplies, meters, jumpers, and parts you’ve swapped in and out of the circuit.

In an attempt to tame this runaway mess, [Raph] came up with this neat modular breadboard system. It hearkens back to the all-in-one prototyping systems we greatly coveted when the whole concept of solderless breadboards was new and correspondingly unaffordable. Even today, combination breadboard and power supply systems command a pretty penny, so rolling your own might make good financial sense. [Raph] made his system modular, with 3D-printed frames that lock together using clever dovetail slots. The prototyping area snaps to an instrumentation panel, which includes two different power supplies and a digital volt-amp meter. This helps keep the bench clean since you don’t need to string leads all over the place. The separate bin for organizing jumpers and tidbits that snaps into the frame is a nice touch, too.

Want to roll your own? Not a problem, as [Raph] has thoughtfully made all the build files available. What’s more, they’re parametric so you can customize them to the breadboards you already have. The only suggestion we have would be that making this compatible with [Zack Freedman]’s Gridfinity system might be kind of cool, too.

The Automatic Battery Charger You Never Knew You Needed

When we saw [Max.K]’s automatic NiMh battery charger float past in the Hackaday tips line, it brought to mind a charger that might be automatic in the sense that any modern microcontroller based circuit would be; one which handles all the voltages and currents automatically. The reality is far cooler than that, a single-cell charger in which the automatic part comes in taking empty cells one by one from a hopper on its top surface and depositing them charged in a bin at the bottom.

Inside the case is a PCB with an RP2040 that controls the whole shop as well as the charger circuitry. A motorised cam with a battery shaped insert picks up a cell from the bin and moves it into the charger contacts, before dumping it into the bin when charged. What impresses us it how slick this device is, it feels like a product rather than a project, and really delivers on the promise of 3D printing. We’d want one on our bench, and after watching the video below the break, we think you will too.

Unique 3D Printer Has a Print Head With a Twist

If you’re used to thinking about 3D printing in Cartesian terms, prepare your brain for a bit of a twist with [Joshua Bird]’s 4-axis 3D printer that’s not quite like anything we’ve ever seen before.

The printer uses a rotary platform as a build plate, and has a linear rail and lead screw just outside the rim of the platform that serves as the Z axis. Where things get really interesting is the assembly that rides on the Z-axis, which [Joshua] calls a “Core R-Theta” mechanism. It’s an apt description, since as in a CoreXY motion system, it uses a pair of stepper motors and a continuous timing belt to achieve two axes of movement. However, rather than two linear axes, the motors can team up to move the whole print arm in and out along the radius of the build platform while also rotating the print head through almost 90 degrees.

The kinematic possibilities with this setup are really interesting. With the print head rotated perpendicular to the bed, it acts like a simple polar printer. But tilting the head allows you to print steep overhangs with no supports. [Joshua] printed a simple propeller as a demo, with the hub printed more or less traditionally while the blades are added with the head at steeper and steeper angles. As you can imagine, slicing is a bit of a mind-bender, and there are some practical problems such as print cooling, which [Joshua] addresses by piping in compressed air. You’ll want to see this in action, so check out the video below.

This is a fantastic bit of work, and hats off to [Joshua] for working through all the complexities to bring us the first really new thing we’ve seen in 3D printing is a long time.

Thanks to [Keith Olson], [grythumn],  [Hari Wiguna], and [MrSVCD] for the near-simultaneous tips on this one.

A Free Speed Boost For Your Pi 5

The world of the overclocker contains many arcane tweaks to squeeze the last drops of performance from a computer, many of which require expert knowledge to understand. Happily for Raspberry Pi 5 owners the Pi engineers have come up with a set of tweaks you don’t have to be an overclocker to benefit from, working on the DRAM timings to extract a healthy speed boost. Serial Pi hacker [Jeff Geerling] has tested them and thinks they should be good for as much as 20% boost on a stock board. When overclocked to 3.2 GHz, he found an unbelievable 32% increase in performance.

We’re not DRAM experts here at Hackaday, but as we understand it they have been using timings from the Micron data sheets designed to play it safe. In consultation with Micron engineers they were able to use settings designed to be much faster, we gather by monitoring RAM temperature to ensure the chips stay within their parameters. Best of all, there’s no need to get down and dirty with the settings, and they can be available to all with a firmware update. It’s claimed this will help Pi 4 owners to some extent as well as those with a Pi 5, so even slightly older boards get some love. So if you have a Pi 5, don’t wait for the Pi 6, upgrade today, for free!

Building Experience and Circuits for Lithium Capacitors

For the cautious, a good piece of advice is to always wait to buy a new product until after the first model year, whether its cars or consumer electronics or any other major purchase. This gives the manufacturer a year to iron out the kinks and get everything ship shape the second time around. But not everyone is willing to wait on new tech. [Berto] has been interested in lithium capacitors, a fairly new type of super capacitor, and being unwilling to wait on support circuitry schematics to magically show up on the Internet he set about making his own.

The circuit he’s building here is a solar charger for the super capacitor. Being a fairly small device there’s not a lot of current, voltage, or energy, but these are different enough from other types of energy storage devices that it was worth taking a close look and designing something custom. An HT7533 is used for voltage regulation with a Schottky diode preventing return current to the solar cell, and a DW01 circuit is used to make sure that the capacitor doesn’t overcharge.

While the DW01 is made specifically for lithium ion batteries, [Berto] found that it was fairly suitable for this new type of capacitor as well. The capacitor itself is suited for many low-power, embedded applications where a battery might add complexity. Capacitors like this can charge much more rapidly and behave generally more linearly than their chemical cousins, and they aren’t limited to small applications either. For example, this RC plane was converted to run with super capacitors.

Balancing Balls With A Touchpad

Energy is expensive these days. There’s no getting around it. If, like [Giovanni], you want to keep better track of your usage, you might find value in his DIY energy meter build.

[Giovanni] built his energy meter to monitor energy usage in his whole home. An ESP32 serves as the heart of this build. It’s hooked up with a JSY-MK-194G energy metering module, which uses a current clamp and transformer in order to accurately monitor the amount of energy passing through the mains connection to his home. With this setup, it’s possible to track voltage, current, frequency, and power factor, so you can really nerd out over the electrical specifics of what’s going on. Results are then shared with Home Assistant via the ESPHome plugin and the ESP32’s WiFi connection. This allows [Giovanni] to see plots of live and historical data from the power meter via his smartphone.

A project like this one is a great way to explore saving energy, particularly if you live somewhere without a smart meter or any other sort of accessible usage tracking. We’ve featured some of [Giovanni’s] neat projects before, too. Video after the break.

Stripping GoPros To The Bone For Model Rocketry

The small size of action cameras has made them a great solution for getting high-quality experimental footage where other cameras don’t fit. GoPros are [Joe Barnard]’s camera of choice for his increasingly advanced rockets, but even the smallest models don’t quite fit where he needs them. They also overheat quickly, so in the video after the break, he demonstrates how he strips and customizes them to fit his required form factor.

[Joe] starts out with a GoPro HERO10 Bones, which is a minimalist version intended for FPV drones. He likes the quality of the 4K 120 FPS video and the fact that he can update the settings by simply holding up a QR code in front of the camera. The case appears to be ultrasonically welded, so careful work with a Dremel is required to get it open. The reveals the control board with an aluminum heat sink plate, and the sensor module on a short ribbon cable. For minimal drag[Joe] wants just the lens to poke out through the side of the rocket, so he uses slightly longer aftermarket ribbon cables to make this easier.

The camera’s original cooling design, optimized for drone airflow, meant the device would overheat within 5 minutes when stationary. To increase the run time without the need for an external heat sink, [Joe] opts to increase the thermal mass by adding thick aluminum to the existing cooling plate with a large amount of thermal paste. In an attempt to increase heat transfer from the PCB, he also covers the entire PCB with a thick layer of thermal paste. Many of the video’s commenters pointed out that this may hurt more than it helps because the thermal paste is really intended to be used as a thin layer to increase the contact surface to a heat sink. It’s possible that [Joe] might get better results with just a form-fitting thermal block and minimal thermal paste.

[Joe] is permanently epoxying three of these modified cameras into his latest rocket, which is intended to fly at Mach 3, and touch space. This may look like a waste of three relatively expensive cameras, but it’s just a drop in the bucket of a very expensive rocket build.

We’ve seen GoPros get (ab)used in plenty of creative ways, including getting shot from a giant slingshot, and reaching the edge of space on a rocket and a balloon.

Electrostatic Puck: Making An Electret

You might have heard of electrets being used in microphones, but do you know what they are? Electrets produce a semi-permanent static electric field, similar to how a magnet produces a magnetic field. The ones in microphones are very small, but in the video after the break [Jay Bowles] from Plasma Channel makes a big electret and demonstrates it’s effects.

Electrets have been around since the 1800s, and are usually produced by melting an insulating material and letting it solidify between two high-voltage electrodes. The original recipe used a mix of Carnauba wax, beeswax, and rosin, which is what [Jay] tried first. He built a simple electric field detector, which is just a battery, LED and FET, with an open-ended resistor on the FET’s gate.

[Jay] 3D printed a simple cylindrical mold and stuck aluminum foil to the outer surfaces to act as the electrodes. He used his custom 6000:1 voltage transformer to hold the electrodes at ~40 kV. The first attempt did not produce a working electret because the electrodes were not in contact with the wax, and kept arcing across, which causes the electric charge to drop off repeatedly. Moving the aluminum electrodes the inner surfaces and a larger distance between the plates eventually produced an electret detectable out to 10 inches.

This was with the original wax recipe, but there are now much better materials available, like polyethylene. [Jay] heated a a block of it in the oven until it turned into a clear blob, and compressed it in a new mold with improved insulation. This produced significantly better results, with an electric field detectable out to 24 inches.

[Jay] also built an array of detectors in a 5×5 grid, which he used to help him visualize the size and shape of the field. He once pulled off a similar trick using a grid of neon bulbs.

When Transistor Count Mattered

Many Hackaday readers have an interest in retro technology, but we are not the only group who scour the flea markets. Alongside us are the collectors, whose interest is as much cultural as it is technological, and who seek to preserve and amass as many interesting specimens as they can. From this world comes [colectornet], with a video that crosses the bridge between our two communities, examining the so-called transistor wars of the late 1950s and through the ’60s. Just as digital camera makers would with megapixels four or five decades later, makers of transistor radios would cram as many transistors as they could into their products in a game of one-upmanship.

A simple AM transistor radio can be made with surprisingly few components, but for a circuit with a reasonable performance they suggest six transistors to be the optimal number. If we think about it we come up with five and a diode, that’s one for the self-oscillating mixer, one for IF, an audio preamplifier, and two for the audio power amplifier, but it’s possible we’re not factoring in the relatively low gain of a 1950s transistor and they’d need that extra part. In the cut-throat world of late ’50s budget consumer electronics though, any marketing ploy was worth a go. As the price of transistors tumbled but their novelty remained undimmed, manufacturers started creating radios with superfluous extra transistors, even sometimes going as far as to fit transistors which served no purpose. Our curious minds wonder if they bought super-cheap out-of-spec parts to fill those footprints.

The video charts the transistor wars in detail, showing us a feast of tiny radios, and culminating in models which claim a barely credible sixteen transistors. In a time when far more capable radios use a fraction of the board space, the video below the break makes for a fascinating watch.

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