Day: March 26, 2025

Tech In Plain Sight: Hearing Aids

March 26, 2025 by 38 Comments

You might think you don’t need a hearing aid, and you might be right. But in general, hearing loss eventually comes to all of us. In fact, you progressively lose hearing every year, which is why kids can have high-pitched ringtones their parents can’t hear.

You’d think hearing aids would be pretty simple, right? After all, we know how to pick up sounds, amplify them, and play them back. But there’s a lot more to it. Hearing aids need to be small, comfortable, have great battery life, and cram a microphone and speaker into a small area. That also can lead to problems with feedback, which can be very uncomfortable for the user. In addition, they need to handle very soft and loud sounds and accommodate devices like telephones.

Although early hearing aids just made sound louder and, possibly, blocked unwanted sound, modern devices will try to increase volume only in certain bands where the user has hearing loss. They may also employ sophisticated methods to block or reduce noise. Continue reading “Tech In Plain Sight: Hearing Aids” →

Build Customized Raspberry Pi OS Images With Rpi-image-gen

March 26, 2025 by 21 Comments

Recently Raspberry Pi publicly announced the release of their new rpi-image-gen tool, which is advertised as making custom Raspberry Pi OS (i.e. Debian for specific Broadcom SoCs) images in a much more streamlined fashion than with the existing rpi-gen tool, or with third-party solutions. The general idea seems to be that the user fetches the tool from the GitHub project page, before running the build.sh script with parameters defining the configuration file and other options.

The main advantage of this tool is said to be that it uses binary packages rather than (cross-)compiling, while providing a range of profiles and configuration layers to target specific hardware & requirements. Two examples are provided in the GitHub project, one for a ‘slim’ project, the other for a ‘webkiosk‘ configuration that runs a browser in a restricted (Cage) environment, with required packages installed in the final image.

Looking at the basic ‘slim’ example, it defines the INI-style configuration in config/pi5-slim.cfg, but even when browsing through the main README it’s still somewhat obtuse. Under device it references the mypi5 subfolder which contains its own shell script, plus a cmdline.txt and fstab file. Under image it references the compact subfolder with another bunch of files in it. Although this will no doubt make a lot more sense after taking a few days to prod & poke at this, it’s clear that this is not a tool for casual users who just want to quickly put a custom image together.

This is also reflected in the Raspberry Pi blog post, which strongly insinuates that this is targeting commercial & industrial customers, rather than hobbyists.

Admit It. You Want This Go-Kart

March 26, 2025 by 17 Comments

Many of us could have been lucky enough to have some form of pedal go-kart in our formative years, and among such lucky children there can have been few who did not wish for their ride to have a little power. Zipping around the neighborhood remained a strenuous affair though, particularly for anyone whose hometown was on a hill. What a shame we didn’t have [Matto Godoy] as a dad then, because he has taken a child’s go-kart and turned it into the electrically-propelled ride of dreams.

Out come the pedals and in goes a wooden floor panel, and at the rear the axle is replaced by a set of hoverboard motors and associated batteries and controllers. The wheels are off-the-shelf wheelbarrow parts, and the 36 V lithium-polymer gives it plenty of go. It looks too small for us, but yes! We want one.

If you want one too, you could do worse than considering a Hacky Racer. And if more motor power is your thing, raid the auto recyclers!