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Recently I got my hands on an intriguing device. It was described to me as a Bluetooth Button, but I couldn’t figure out how it worked because no instructions were provided. It was given out at an event, which meant that this was quite a low cost device. I decided to take it apart for analysis. Research There are several iterations of these devices floating on the market. One of them is the iTag device, or the camera shutter Bluetooth device. These devices are available from eBay or Aliexpress from $3 to $1. From some online chatter, it seems like dollar stores actually stock these devices. Because they are so cheap, some people have repurposed them as single purpose buttons, for example, to track inventory or to activate a device remotely. ...

What is Thread? Thread is a self-healing mesh network that uses the same radio as Bluetooth 5.0. It supports external commissioning, encrypted communications by default, and is simple to set up. The great thing about Thread is that a lot of the low level addressing and networking is already done for you, so you are free to implement your network quickly and easily instead of futzing around with configurations. How to get started My recommendation is to set up a Raspberry Pi Border Router. An alternative is to use the Raspi image that Nordic has already set up, but I ran into a few issues booting the Raspberry Pi with the image, so I decided to go with the docker image that Google has provided. ...

I recently got very interested in controlling the amount of power my boards use because between transmitting data and using battery powered devices, there isn’t a whole lot of energy to spare if you don’t want to be tied to a wall wart. Adafruit and Sparkfun both sell the TPL5110 breakout boards that essentially act as delay switches that start a timer when a switch closes. The system shuts off the power by sending a signal to the trigger pin, which opens the circuit. When the period is up, the switch will open again. However, because it is a little expensive for me, I was looking around for alternatives, and this little board caught my eye: ...

Lessons Learned Locating holes for PCBs and for standoffs Using traces to separate positive and negative tracks Hinge design with nuts and bolts This is a lamp that I bought a few years ago for my table. I have not used in awhile and I decided to open it up to take a peek at its innards. Luckily for me, this lamp was held together mostly with screws and tabs, so it was relatively non-destructive to take it apart. ...

How I automated my home with MQTT. This started when I decided to implement an Network Attached Storage to use a hard drive that I had lying around as a DIY solution to Dropbox’s capping of devices. My project worked perfectly, but it seemed like such a waste leaving a Raspberry Pi 3B+ running constantly to manage an NAS that I don’t use all that often. So I decided to start on a project to automate and collect data around my room. Besides, I have an embarrassment of Raspberry Pis’ that are just waiting to put into service. ...

Tldr; Build a local Dropbox-like system on a Raspberry Pi without spending hundreds on a dedicated NAS (Network attached storage). [Updated for 2020] In 2019, Dropbox limited the number of devices you can connect in a free account, and as someone who has multiple computers (don’t ask), this made me pause. I was happy living on the 5GB from Dropbox for many years. Did I really need to upgrade to a 1TB (2TB as of 2020) cloud storage solution? ...

For future reference Telling people to find a new job if they are not satisfied with their current one is not helpful. If they could, they would. Often the reason why they can’t change jobs are due to existing commitments, inability to relocate, or the lack of funds to do so. Appeals to morals and values. More commentary than discussion of the facts. Many unsupported assertions. The government should play an active role in providing alternatives in education, healthcare, and finance. The coupling of political interests and economics in the US is very strong. Frequently uses the phrase ‘one dollar one vote’. Thoughts I found this book to be too narrowly focused on the now. While it does a good job of tying together politics and economics, there is a lot of commentary on the current US administration. This book is good for those who want to understand US as it currently is, but the solutions and comments laid out here are very specific to US today.

The SunBar is light alarm, following my development of light-based alarms which I have found to be quite effective in establishing a set routine of waking up early. The earlier versions were based off: a breadboarded circuit, a protoboard circuit with an ATTiny85, and an Arduino Shield. Protoboard circuit The protoboard version was designed to take 12V and regulate it down to 5V for the ATTiny85. A N-Channel Mosfet was used to control the brightness of the LED strip. ...

I love audiobooks. They allow me to enjoy books while allowing me to other tasks. However, audio content is not always available. Small snippets of news or articles are great for listening to as they don’t require much attention, but because of their transient nature, they are very rarely available in audio form. This could also benefit those who might find articles too tiring to read because of the screen or other issues that prevents them from reading digital content. ...

TLDR: This post documents my lessons on building a flight altimeter for model rocketry. It is built with solving a few pain points in mind: 1. Output basic diagnostic data when it is installed in the AV bay. 2. Collect orientation data. I realized that I would always use the same components for my flight computers/altimeters: 9 DOF sensor, altimeter, SD card storage. Having all of these already on a single board would prove immensely helpful. ...