How To Get Into Cars: Basic Maintenance

February 12, 2020 by 84 Comments

So, you’ve decided you want to get into cars. After much research and deliberation, you’ve bought yourself a sweet project car, and can’t wait to get down to work. First things first – it’s time to learn about basic maintenance!

Get It Right For A Good Time

Doing necessary maintenance on time is key to enjoying your project car. Too many gearheads know the pain of a neglected beast that spends more time up on jackstands than out on the road. Buying the right car, and keeping a close eye on what needs to be done, will go a long way to improving your experience and relationship with your ride.

If you’ve just bought a car, no matter how good things look, it’s a good idea to go through things with a fine-tooth comb to make sure everything’s up to scratch. This can avoid expensive damage down the line, and is a great way to get your feet wet if you’re new to working on cars. Here’s a bunch of easy jobs you can tackle as a novice that will keep your ride in tip-top condition. Continue reading “How To Get Into Cars: Basic Maintenance” →

Sniffing Signals To Teach Old Speakers New Tricks

February 12, 2020 by 24 Comments

Like many of the stories you’ll find on these pages, this one starts with a user being annoyed about their device’s inability to perform a simple task. All [Jay Tavares] wanted was for his Bose Cinemate speakers to turn themselves on and off as needed. It seems like a reasonable enough request, and indeed, is exactly the point of HDMI’s Consumer Electronic Control (CEC) feature. But in this case, it would take a bit of custom hardware to get similar functionality.

Unfortunately, the speakers [Jay] has only support optical audio; so any interoperability with HDMI-CEC (hacked or otherwise) was immediately out the window. Still, he reasoned that he should be able to detect when the TOSLINK audio source is actually active or not, and give the speaker system the appropriate signal to either power on or shut down. You might think this would require some kind of separate stand-alone device, but as it turns out, all the necessary information was available by reverse engineering the connection between the receiver and the subwoofer.

After some investigation, [Jay] found that not only was the content of the TOSLINK audio source being sent over this DB9 cable, but so were the control signals required to turn the system on and off. So he designed a simple pass-through device with an ATtiny85 and a couple passives that latches onto the relevant lines in the cable.

When audio is detected over the optical connection, the MCU will inject the appropriate signals on the control line to simulate the user pressing the “Power” button the remote. When the chip hasn’t detected audio after 10 seconds, it sends the signal to shut the speakers off.

While [Jay] notes he can’t guarantee this works on anything other than the particular Bose Cinemate GS Series II system he has, we’d be willing to bet the concept could be adapted to other models or even brands that use a similar cable to link their principle components. If all else fails, you could always add an ESP8266 to your sound system and control it over WiFi.

Concrete Solder Squid Is A Solid Solution

February 12, 2020 by 12 Comments

Although it’s possible to buy a soldering setup out of the box, the one that works for you will likely develop over time. Honestly, it may never stop evolving. Sure, you can start with el-cheapo helping hands or a nice hobby vise, but it probably won’t end there. Why? Because no one of these tools will be right for all applications, unless you plan to solder the same thing over and over again. Sometimes it’s just easier to alligator clip a board in place than to slowly manipulate the jaws of a vise, but those helping hands have such a limited range of motion.

Have you been meaning to build a soldering squid out of coolant hose because that stuff just looks so dang cool and bendy? Well, then let Hackaday alum [JeremySCook] show you how it can be done. A few years ago he built a similar squid with a wooden base, but it just isn’t heavy enough, so he redesigned it with a concrete base. He took the opportunity to make some nice tweaks, like zip-tying a small PC fan and 9 V to make an endlessly repositionable ventilation system, and adding a big clip in the back for extra stability while soldering. And of course, threading the solder spool on to one of the hoses is genius.

If you follow [Jeremy] at all, you know he’s been playing around with concrete for a while now, and it’s neat to see him cement his devotion to the stuff by using it in the pursuit of better tools. He’s got the files for the printed mold up on GitHub, and the build video after the break should be all set up by now.

Not custom enough for you? Fire up that printer and make your own ball and socket arms.
Continue reading “Concrete Solder Squid Is A Solid Solution” →

Custom Firmware For Cheap Smart Bulbs Is A Cinch To Tinker With

February 11, 2020 by 14 Comments

It’s the end of another decade, and while we don’t have real hoverboards, flying cars, or affordable dental care, we do have multicolored lightbulbs you can control over WiFi. [Don Howdeshell] picked up a couple of cheap Merkury branded units in a Black Friday sale, and quickly set about hacking them.

By and large, many of these bulbs are manufactured by various companies and rebranded for whoever happens to place an order. The bulbs tend to use the Tuya IOT ecosystem. Based on the ESP8266, reflashing the bulbs with custom firmware is simple, thanks to the Tuya Convert project. Using a Linux computer with a WiFi card running in Access Point mode, it spoofs a server that tricks the Tuya product into downloading a firmware update. From there, the bulb is an open book, ready to do your bidding.

One of [Don]’s attempts didn’t go so swimmingly, however. Flashing the firmware failed and the bulb was non-functional. [Don] elected to to a teardown, photographing it for our perusal, before hooking up to the ESP8266 directly over its serial interface. From there, it was simple to reprogram the bulb with Tasmota firmware, getting it back up and running.

Security alone is a great reason for running your own firmware on IoT devices. It never hurts to know what you’re connecting to your network!

Name That Unknown RF Signal With A Little FFT Magic

February 11, 2020 by 27 Comments

Time was once that the amateur radio bands were an aurally predictable place. Spinning the dial up and down the bands, one heard familiar sounds – the staccato of Morse, the [Donald Duck] of sideband voice transmissions, and the occasional flute-like warble of radioteletype signals. Now, the ham bands are full of exotic signals encoding all manner of digital signals, each one with a unique sound and unique demodulation needs. What’s a ham to do?

Help is on the way. [José Carlos Rueda] has made progress toward automatically classifying unknown signals by modifying a Shazam-like app. Shazam is a popular smartphone app that listens to a few seconds of a song, creates an audio fingerprint of it, and searches a massive database of songs for a match. [Rueda] used a homebrew version of the app to search a SQL-lite database of audio fingerprints populated not with a playlist of popular music, but with samples from every known signal type in the Signal Identification Wiki. The database contains hashes for an FFT of each sample, which can be easily searched. With a five to ten second sample of a signal, captured either live over a microphone or from a recording,  he is able to identify the signal automatically.

Whether it be the weird, dissonant wail of PSK-31 or the angry buzzing of PACTOR, the goings-on across the bands no longer have to remain a mystery. We really like the idea here, and wonder if it can be expanded upon to visually decode signals based on their waterfall signatures using TensorFlow. There are some waterfall examples in [Danie Conradie]’s excellent article on RF modulation that could get you started.

[via RTL-SDR.com]

Portable Pizza Oven Does The Job, And Fast

February 11, 2020 by 21 Comments

Pizza ovens are a fun thing to have in your back yard, and often wood is the fuel of choice for that smoky, rustic charm. However, [Andrew] is a fan of speed, leading him to prefer propane when it comes time to make a pizza. This guided his portable pizza oven build, with impressive results.

Hot, fresh pizza cooked in just minutes. Pretty attractive, huh?

With this build, [Andrew]’s goal was to have a portable oven that didn’t sacrifice on performance. Commercial offerings were easy to lug around, but tend to cool down too much after cooking a pie, leading to lengthy waits for the oven to return to temperature. Not content to wait, [Andrew] specified his build with two custom tube burners to heat the floor, with separate jet burners to heat the cavity. When two jets proved too much, he refined the design to just one to improve efficiency and reduce carbon build up.

The Instructable is a great read, covering both the design of the oven as well as the necessary techniques to cook high-quality Neapolitan pizzas in minutes flat – right down to the selection of flour and proper insertion techniques to avoid sticking. The home pizza enthusiast could learn a lot here, and it’s great to see [Andrew] continue to improve on his earlier designs. Video after the break.

This is only the most recent of many pizza ovens to grace these pages. How about one in a beer keg?

Continue reading “Portable Pizza Oven Does The Job, And Fast” →

Build Your Own Active Load

February 11, 2020 by 29 Comments

When it comes to testing power supplies, it’s useful to have a dummy load to put the gear through its paces. While it’s possible to just use some old heating elements or other big resistors, an active load can provide more control over the process. [Charles Ouweland] found himself in need of just such a piece of gear, and decided to build his own.

Commercial units often pack in a raft of features, operating in different modes from constant resistance, constant power, and constant current. For [Charles]’s needs, just constant current would be fine, and thus the design progressed around this constraint.

The IRFP250 MOSFET specified in the build can dissipate up to 190W, but as it heats up, this is reduced. In this design, cooled by a heatsink and PC fan, [Charles] estimates 120W continous output is a safe limit. It’s combined with an LM358 op-amp and TL431A reference voltage source to act as a current sink, controllable between 0 and 10 amps.

We’re sure that the new hardware makes testing power supplies a cinch for [Charles], and it’s always good to have a strong understanding of the workings of your own test gear. We’ve seen open-source designs in this space, too!