An alarm clock with a Nixie tube display

Retro Alarm Clock With Nixies Is Thoroughly Modern Inside

December 10, 2022 by 12 Comments

We feature a lot of clocks here at Hackaday, but alarm clocks seem to be less popular for some reason. Maybe that’s because no-one enjoys being woken up in the morning, or simply because everyone uses their smartphone for that purpose already. In any case, we’re delighted to bring you [Manuel Tosone]’s beautiful Nixie tube alarm clock that cleverly combines modern and classic technologies in a single package.

An alarm clock with a Nixie tube display, openedThe clock and alarm functionalities are implemented by a PIC24 microcontroller on a custom mainboard. It keeps track of time through its real-time clock with battery backup, and plays a song from an SD card when it’s time to wake up. A 2 x 3 W class D audio amplifier plus a pair of stereo speakers should be able to wake even the heaviest sleepers.

Of course, the real party piece is the clock’s display: four IN-4 Nixie tubes show the time, with neon tubes indicating the day of the week. The 180 V needed for the Nixies is generated by an MC34063A-based boost converter, which also powers the neon tubes.

Instead of using the standard current-limiting resistor for each Nixie tube, [Manuel] designed an array of transistor-based current sources: this enables linear control of the tubes’ brightness, and should keep the amount of light constant even as the tubes age. The individual segments are switched by SN75468 Darlington arrays, with no need for those hard-to-find SN74141 drivers.

The mainboard and the display are housed inside a 3D-printed case that mimics the style of 1980s digital alarm clocks, but with a nice 1970s twist courtesy of those Nixie tubes. [Manuel]’s GitHub page has all the schematics as well as extensive documentation describing the circuit’s operation — an excellent resource if you’re planning to build a Nixie project yourself. If Nixies aren’t your thing, you can also make an alarm clock with a VFD tube, or even roll your own luminous analog dial.

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Snooping On Starlink With An RTL-SDR

September 23, 2022 by 21 Comments

With an ever-growing constellation of Starlink satellites whizzing around over our heads, you might be getting the urge to start experimenting with the high-speed internet service. But at $100 or more a month plus hardware, the barrier to entry is just a little daunting for a lot of us. No worries, though — if all you’re interested in is tracking [Elon]’s birds, it’s actually a pretty simple job.

Now, we’re not claiming that you’ll be able to connect to Starlink and get internet service with this setup, of course, and neither is the delightfully named [saveitforparts]. Instead, his setup just receives the beacon signals from Starlink satellites, which is pretty interesting all by itself. The hardware consists of his “Picorder” mobile device, which sports a Raspberry Pi, a small LCD screen, and a host of sensors, including an RTL-SDR dongle. To pick up the satellite beacons, he used a dirt-cheap universal Ku-band LNB, or low-noise block downconverter. They’re normally found at the focal point of a satellite TV dish, but in this case no dish is needed — just power it up with a power injector and point it to the sky. The signals show up on the Picorder’s display in waterfall mode; curiously, the waterfall traces look quite similar to the patterns the satellites make in the night sky, much to the consternation of astronomers.

Of course, you don’t have to have a Picorder to snoop in on Starlink — any laptop and SDR should work, despite [saveitforparts]’ trouble in doing so. You shouldn’t have much trouble replicating the results by following the video below, which also has a few tips on powering an LNB for portable operations.

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Simple Breadboard SDR For Shortwave

August 26, 2022 by 19 Comments

One of the best ways to learn about radios is to build your own, even in the age of cheap SDR dongles. [Aniss Oulhaci] demonstrates this with a simple HF SDR receiver built on a breadboard.

The receiver takes the form of a simplified Tayloe detector. An RF preamp circuit amplifies the signal from a shortwave antenna and feeds it into a 74HC4066D analog switch, which acts as a switching mixer. It mixes the input signal with the local oscillator’s I and Q signals to produce the intermediate frequency signals. The local oscillator consists of a SI5351 clock generator with a 74HC74D flip-flop to generate the I and Q pair. The signals pass through a low pass filter stage and get amplified by an LM358 op amp, resulting in the IQ signal pair being fed to a computer’s stereo sound card.

An Arduino is used to control the SI5351 clock generator, which in turn is controlled by the same program created for the SDR Shield. With the audio signal fed to HDSDR, [Aniss] was able to pick up a shortwave radio broadcaster.

While this is by no means a high-performance receiver, building an SDR on a breadboard is still a great weekend project, with plenty of potential for further experimentation.

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Everything You Wanted To Know About SDRAM Timing But Were Afraid To Ask

August 5, 2022 by 9 Comments

One of the problems with being engaged in our hobby or profession is that people assume if you can build a computer out of chips, you must know all the details of their latest laptop computer. Most of the memory we deal with is pretty simple compared to DDR4 memory and if you’ve ever tried tweaking your memory, you know a good BIOS has dozens of settings for memory. [Actually Hardcore Overclocking] has a great description of a typical DDR4 datasheet and you can watch it in the video below.

Of course, he points out that knowing all this really doesn’t help you much with memory overclocking because you can’t really predict the complex effects without trial and error. However, most of us like to understand the knobs we are randomly twisting. On top of that, one theme of the video is that DRAM is dumb and simple. If you’ve ever thought about using it in a project, this might be a good place to start.

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Bringing Some Discipline To An SDR Transmitter

July 13, 2022 by 16 Comments

The proliferation of software-defined radio (SDR) technology has been a godsend for RF hobbyists. SDR-based receivers and transmitters have gotten so cheap that you’ve probably got a stick or two lying around your bench right now — we can see three from where we sit, in fact.

But cheap comes at a price, usually in the form of frequency stability, which can be prohibitive in some applications — especially amateur radio, where spectrum hygiene is of the utmost concern. So we were pleased to see [Tech Minds] tackle the SDR frequency stability problem by using a GPS-disciplined oscillator. The setup uses an ADALM-PLUTO SDR transceiver and a precision oscillator from Leo Bodnar Electronics. The oscillator can be programmed to output a rock-solid, GPS-disciplined signal over a wide range of frequencies. The Pluto has an external oscillator input that looks for 40 MHz, which is well within the range of the GPSDO.

Setup is as easy as plugging the oscillator’s output into the SDR’s external clock input using an SMA to UFL jumper, and tweaking the settings in the SDR and oscillator. Not all SDRs will have an external clock input, of course, so your mileage may vary. But if your gear is suitably equipped, this looks like a great way to get bang-on frequency — the video below shows just how much the undisciplined SDR can drift.

Like any good ham, [Tech Minds] is doing his bit to keep his signals clean and on target. His chief use case for this setup will be to work QO-100, amateur radio’s first geosynchronous satellite repeater. We’ve got to say that we hams living on the two-thirds of the globe not covered by this satellite are just dying to get a geosynchronous bird (or two) of our own to play with like this.

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Hackable OSHW CardClock Demands Attention

July 12, 2022 by 12 Comments

When examining a project, it’s easy to be jaded by a raw parts list. When the main component is an ESP8266, we might say “oh, another 8266 project. yawn!” But we’re certain that when you take a look at [Will Fox]’s Foxie CardClock, it’ll surely grab your attention.

As if all those beautiful LEDs weren’t enough, the rest of the device’s specifications are quite impressive. The core components might be common, but what often separates such projects is the software. With Over The Air updates supported via ArduinoOTA, updates are a snap. A light sensor helps to keep all those LEDs at a sane level, and a once-per-minute synchronization via NTP keeps the time accurate. Even if power is lost, a super-capacitor can hold the time accurate for up to two days with the built in RTC module. There’s even provisions for setting the time using the buttons on the front panel should you want to keep the gadget offline.

The entire project is open source, with the hardware released under the CERN Open Hardware Licence Version 2 and the firmware source code distributed as GPLv3. Users are encouraged to hack and modify the design, and all the information you need to build one of your own is available in the project’s GitHub repository. [Will] also offers a pre-assembled version of the clock for just $45 USD, but unfortunately it seems to be out of stock at the time of this writing.

If credit card sized hacks are your chosen area of interest, you will appreciate this crystal radio made from an actual Credit Card. Thanks to [Abe] for submitting the Tip!

A Honda car behind a gate, with its turn signals shown blinking as it's being unlocked by a portable device implementing the hack in question. Text under the car says "Rolling Pwned".

Unlock Any (Honda) Car

July 8, 2022 by 76 Comments

Honda cars have been found to be severely  vulnerable to a newly published Rolling PWN attack, letting you remotely open the car doors or even start the engine. So far it’s only been proven on Hondas, but ten out of ten models that [kevin2600] tested were vulnerable, leading him to conclude that all Honda vehicles on the market can probably be opened in this way. We simply don’t know yet if it affects other vendors, but in principle it could. This vulnerability has been assigned the CVE-2021-46145.

[kevin2600] goes in depth on the implications of the attack but doesn’t publish many details. [Wesley Li], who discovered the same flaw independently, goes into more technical detail. The hack appears to replay a series of previously valid codes that resets the internal PRNG counter to an older state, allowing the attacker to reuse the known prior keys. Thus, it requires some eavesdropping on previous keyfob-car communication, but this should be easy to set up with a cheap SDR and an SBC of your choice.

If you have one of the models affected, that’s bad news, because Honda probably won’t respond anyway. The researcher contacted Honda customer support weeks ago, and hasn’t received a reply yet. Why customer support? Because Honda doesn’t have a security department to submit such an issue to. And even if they did, just a few months ago, Honda has said they will not be doing any kind of mitigation for “car unlock” vulnerabilities.

As it stands, all these Honda cars affected might just be out there for the taking. This is not the first time Honda is found botching a rolling code implementation – in fact, it’s the second time this year. Perhaps, this string of vulnerabilities is just karma for Honda striking down all those replacement part 3D models, but one thing is for sure – they had better create a proper department for handling security issues.