20 | November | 2022

These days, sending a photo to someone else is as easy as pulling out your smartphone and sending it via email or text. It’s so simple a child can do it, but that simple user experience masks a huge amount of complexity, from the compression algorithms in the phones to the massive amount of distributed infrastructure needed to connect them. As wonderful and enabling as all that infrastructure can be, sometimes it’s just too much for the job.

That seems to have been the case for [Dzl TheEvilGenius], who just wanted to send a low-resolution image from a remote location. It turns out that hams solved that problem about 70 years ago with slow-scan TV, or SSTV. While most of the world settled down in front of “I Love Lucy” on the regular tube, amateur radio operators figured out how to use their equipment to send pictures around the world. But where old hams had to throw a considerable amount of equipment at the problem, [Dzl] just used an ESP-32 with a camera and some custom code to process the image. The output from one of the MCU’s GPIO pins is a PWM audio signal that can be fed directly into the microphone input of an inexpensive portable transceiver.

To decode the signal, [Dzl] used one of the many SSTV programs available. There is no mention of the receiver, although it could be pretty much anything from another Baofeng to an SDR dongle. The code is available in the article, as is an audio file of an encoded image, if you just want to play with the receiving and decoding side of the equation.

We could see something like this working for a remote security camera, or even for scouting hunting grounds. If you want to recreate this, remember you need a license if you want to broadcast on the ham tapes – relax, it’s easy.

We love retrocomputing and tiny computers here at Hackaday, so it’s always nice to see projects that combine the two. [Eivind]’s TinyLlama lets you play DOS games on a board that fits in your hand.

Using the 486 SOM from the 86Duino, TinyLlama adds an integrated Crystal Semiconductor audio chip for AdLib and SoundBlaster support. If you populate the 40-PIN Raspberry Pi connector, you can also use a Pi Zero 2 to give the system MIDI capabilities when connected to a GY-PCM5102 I²S DAC module.

Audio has been one of the more difficult things to drive on these little 486s, so it’s nice to see a simple, integrated solution available. [Eivind] shows the machine running DOOM (in the video during the break) and boots up Monkey Island at the end. There’s a breakout board for serial and PS/2 mouse/keyboard, but he says USB accessories work well if you don’t want to drag the Model M out of the closet.

Looking for more projects using the 86Duino? Check out the ISA sound card on the 86Duino or use an 86Duino with a graphics card.

Continue reading “TinyLlama is a 486 in your pocket” →

When it comes to repairability of electronic devices, a lot depends on how helpful the original manufacturer is. Some make repairs very easy by publishing detailed service manuals and selling spare parts. Others keep everything under wraps to protect their intellectual property rights, turning even a supposedly simple solution into a reverse engineering test. When [BuyItFixIt] got his hands on a FLIR multimeter-thermal camera combination instrument with a broken screen, he quickly learned that FLIR was firmly in the “all our designs are top secret” camp and wouldn’t even tell him what kind of screen they had used.

Not to be deterred, [BuyItFixIt] took the meter apart and tried to figure out what went wrong. The signals from the microprocessor seemed to reach the display OK, so the fault was somewhere in the display itself. The screen’s part number didn’t return any useful results online, but AliExpress had a very similar screen available with a slightly different part number. This screen seemed to work at first, but the instrument then got caught in a boot loop.

Unlike FLIR, the supplier of the replacement screen was happy to provide a data sheet, and even had one available for the original FLIR part. With this new information [BuyItFixIt] was able to deduce that the new display was not outputting one signal that the processor expected to see, causing it to reset itself. A simple solution was to connect the corresponding pin to a PWM signal from the backlight controller, tricking the CPU into thinking the correct display was connected.

In this case, a $12 monitor and a simple piece of wire was enough to bring an expensive instrument back to life, but things aren’t always that simple. More complex machines can take weeks to troubleshoot, even if parts are available. If not, you may even have to design your own. Continue reading “Cheap screen fix brings thermal camera to life” →

For those who don’t know, Gaggia is a company that manufactures a range of affordable ‘entry-level’ espresso coffee machines that offer good quality espresso machines at affordable prices. The entry-level machines do not offer fine-grained control over temperature, pressure and steam, and this is where the Gagguino project comes in.

The Gagguino project is an “aftermarket” modification of many espresso machines, such as the Gaggia classic and Gaggia classic pro. The most important additions are a MAX6675 thermocouple module paired with a K-Type thermocouple sensor for closed-loop control over temperature. Options to add an AC dimmer module that attaches to the pump motor and an XDB401 pressure sensor with a range of 0 Mpa to 1.2 Mpa, installed in-line between the pump and the boiler, provide additional closed-loop control over the pressure and flow profiling. Load cells can be attached to the drip tray to provide feedback on the pour weight with a Nextion 2.4″ LCD touchscreen providing the user interface for profile selection and other interactivity. The project offers a “base” modification using an Arduino Nano as the microcontroller, in keeping with its namesake , but has an option for an STM32 Blackpill module that can provide more functionality beyond the scope of the Nano.

The Gagguino project is open source with code and extensive documentation available on GitHub. There is also a Discord community for those who want help with the build or who want to share their passion for DIY espresso modding with Gagguino. Espresso machine hacking is a favorite of ours, and we’ve featured many projects on espresso machine builds and mods, ranging from PID control of classic espresso machines to beautifully minimal, closed-loop homebrew espresso machines.

Video after the break!

Continue reading “Home brewed espresso machine modding with Gagguino” →

[Fraens] has designed a number of amazing 3D printed machines and made great videos showing how they work. The last part was an automatic cigarette stopper, and it has a series of rather complex movements, and somehow manages to get the job done.

While [Fraens] usually uploads STL files for all his machines, this one is banned! Selling automatic cigarette lighters is illegal in Europe, and it’s not clear how close the legal edge is to posting them on Thingiverse. So until the legal dust settles, you’ll have to be content with the awesome video, also embedded below.

But honestly, devil sticks aren’t good for your health anyway, and you’re probably just in for the mechanical stuff. Think about the problem for a moment – you have a container of tobacco fibers that everyone likes to stick together, and you need to wrap them in a lightly pinched paper tube. These pipes are also not easy to handle. The solution to both of these requires solenoid operated tappers that stir both into place.

There’s also a 3D-printed rack and pinion to do the sliding, and a cool stepper-driven turret mechanism to put the blanks in just the right place. The machine relies heavily on 3D printing, but also on simple hardware store parts such as aluminum and brass tubes. [Fraens]the builds are always simple, but at the same time very smooth, and you’ll learn a lot from seeing everything fit together.

And when you’re done, check out someone else from [Fraens]. We have been impressed with his sewing machine, braiding machine and even a power loom.

Continue reading “See the banned cigarette machine in action” →