nabilt

I had claude write an mcp server to talk to my scope since most are connected over Ethernet. It was pretty fun.

https://netliststudio.com/articles/2026/02/23/claude-oscillo...

That would simplify things. How do nodes usually identify themselves to be able to join the network? Maybe a QR code?

I think most ZigBee and Thread chips use 2.4 GHz which limits distance. A lot of water meters are underground on the front yard somewhere so sub gigahertz radio would penetrate better. The modulation scheme of LoRa also allows for greater distance at the cost of data rate. It's also super low power.

So if I understand correctly, they used hard coded constants to generate keys that only have 44 bits of entropy, which is brute forcible for $10, but you have to do it per device. They presumably did this to make pairing the bridge and sensor easier while not using a static key for all devices. Not the worst compromise I guess.

I've been working on an open source solution on and off for a number of years called http://y-drip.com. It uses Wi-Fi so battery life is only a few months and range is limited. My next design is probably going to use LoRa, but this complicates things a lot because now I have two devices (bridge and sensor) that need to be paired, support over-the-air updates, etc.

What's the best way to have them share keys without adding expensive hardware like Bluetooth or NFC. The sensor also needs to be waterproof so there's no exposed ports. Increasing from 44 bits to 128 would help, but if the key generation is done over the air it can be sniffed right?

I built (and currently testing) a 4 port automated PCB test & programming tool. I needed a way to produce a bunch of PCBs efficiently and couldn't find a solution that was flexible and didn't cost many thousands of dollars. I made a simple tool to solve this.

Features

    - 4-channel DUT interface with individual power control via TPS22992
    - JTAG multiplexer for programming (not exclusive to JTAG)
    - Power monitoring using PAC1954 for per-channel current/voltage measurement
    - Raspberry Pi Pico for control logic and automation
    - USB interface through Pi Pico USB-CDC for host communication (1 port for each DUT)
    - 1.8V - 5V IO support
    - MicroPython support for test script automation

https://www.youtube.com/watch?v=NKTlRVKJuS8&t

https://github.com/Netlist-Studio/dut_hub_hw

Very cool project. Congrats. I will be trying this out.

Two other project I saw that are somewhat related for those interested:

1. reddit community (r/xteinkereader) building an OS like ebook reader app for a small chinese ereader based on esp32-s3

2. Linux port for the esp32-s3. Interestingly, the S3 has an MMU but I don't think it was used in this project.

https://github.com/ESP32DE/Boot-Linux-ESP32S3-Playground?tab...

For those that want more details on how the software works, this guy goes into a bit more detail for his version

Fluid simulation pendant https://mitxela.com/projects/fluid-pendant

https://www.youtube.com/watch?v=jis1MC5Tm8k

If you just want a simple UI editor and don't want to pay for the official tool, give GUI Glider from NXP a try.

https://www.nxp.com/design/design-center/software/developmen...

Super impressive project, especially for what seems to be your first embedded project. I haven't played with microPython/uOTA so this was an interesting read.

Since you mentioned the water meter Flume, I wanted to shamelessly plug my open source water meter that I'm currently developing. It also uses the ESP32 so I thought you might be interested.

Main page. https://y-drip.com/

Docs: https://y-drip.com/docs/site/v0.4/

I started working on my opensource water meter again (https://y-drip.com/). Hardware is basically done so I'm working on the backend website for those that don't want to setup their own server. More technical details here: https://hackaday.io/project/191398-ydrip

  Location: Toronto
  Remote: Yes
  Willing to relocate: Yes
  Technologies: C, Python, JavaScript, HTML, Qualcomm Snapdragon, STM32, AVR, ESP32, Silicon Labs Gecko, Nordic nRF
  Résumé/CV: https://nabil.me/wp-content/uploads/2024/08/nabil_tewolde_resume.pdf
  Email: work@[domain above]

---

I'm a seasoned software engineer with extensive experience in embedded systems, real-time communication, and full-stack development. My background includes designing innovative hardware and software solutions for various applications.

Key Projects:

    - Real-time Audio Communication Device: Developed a device supporting 16 participants over 700 meters with 18-hour battery life using STM32 and Silicon Labs EFR32.
    - Android ROM Customization: Customized Android ROM for a video kiosk, added native USB camera support, and developed an over-the-air A/B update method.
    - Innovative Water Meter Solution (Y-Drip): Designed a product for real-time water usage data and leak detection with ultra-low power consumption.
    - Full Stack Development (Scalp Radar): Created a SAAS website for futures traders using Python, Django, and C#, with an automated license management system.

I'm currently seeking opportunities to leverage my skills in innovative projects, whether in embedded systems, software development, or full-stack applications. Open to remote work or on-site positions.

Hey HN,

I recently launch a side project selling software on Shopify and needed a way to for users to manage their software license. Shopify's sample Django app was out dated and didn't implement all of the security features so I've improved it and wrote a guide on how to set it up.

I've found Shopify to be a good platform for selling software minus a few things like subscriptions. It's nice to have most of the e-commerce features like discount codes, analytics, order management taken care of. The only limitation is their free subscription management app is very limited so you might need to pay or build an app to take care of that.

Hopefully, this should give you a head start on adding custom functionality to your next Shopify side project.

Thanks, good to know. I may need to request a 3A 1U in that case.

I didn't know iDRAC could measure real time power usage. Pretty amazing.

This is a pretty cool solution. I didn't know the capabilities of USB4 before this.

The comparison with the Dell r630 power numbers got me interested since I just purchased a Dell r430 to host my site so I decided to benchmark mine.

Specs:

  * 2x Xeon E5-2680 v3 (same CPU)
  * 64GB RAM
  * 2x power supply (can't remember if it's 500W or 750W each and too lazy to look)
  * 1 SSD & 1 7300 RPM HDD
  * Ubuntu server 22.04.3 LTS

Using a Kill-A-Watt meter I measure ~100 watts after boot. Running sysbench (sysbench --test=cpu --threads=12 --cpu-max-prime=100000 --time=300 run) I get up to ~220 watts.

If my calculations are correct that's 72 kW per day or $11.05 per month at idle:

  0.1 kW * 24 hours * 30 days = 72 kWh
  72 kWh * 15.34 cents/kWh = $11.05 

and 158.4 kW or $24.3 per month during load:

  0.22 kW * 24 hours * 30 days = 158.4 kWh
  158.4 kWh * 15.34 cents/kWh = $24.3

I'm not sure of OP's use case, but these numbers are probably more realistic than using the max wattage of the power supply for most people. I will still be hosting in a co-location for the reliable internet and so I can sleep without the sound of a jet engine taking off. Those fans are loud!

Thanks. Detecting slow leaks while also conserving battery life is tricky so I opted to do it in hardware with digital logic. I keep a count of all of the low speed revolutions of the magnet inside of the brass housing. It needs more testing, but it seems to work for now.

Someone mentioned https://inventree.org which looks cool, but there is no distributor API connections AFAIK. I really wanted to ability to scan my Digikey bags and have it auto fill all of the parameters so I made a super basic app to do that. I'm planning on open sourcing it once I clean it up.

Strange. That's one of the reasons my leak threshold is customizable. My city water meter has an LED that turns on when it detects a leak, but I've never seen it work.

Interesting. Do you mean the leak is intermittent and Flume isn't able to detect it? I would love to know more.

I'm building an open source water meter to detect costly water leaks and track your water usage. The hardware design is flexible enough to easily repurpose it for measuring residential gas and electricity meters, as well as any signal that requires continuous reading while maintaining a long battery life.

https://y-drip.com

Follow the development process here:

https://hackaday.io/project/191398-ydrip

I used a similar screen to display the user interface for my DIY reflow oven. The raspberry Pi and Linux is overkill for this project, but it's so much easier building a GUI than on a microcontroller.

https://nabil.me/2020/12/01/diy-reflow-oven-w-exhaust-build-...

Something interesting I learned during one of his seminars was that breathing exercises can go a long way in providing most of the benefits. A lot of the media coverage focuses on cold exposure, but deep breathing is really the the core of the message. This is great because it means the barrier to entry is much lower since we all don't need to fill up our tubs with ice every week.

If you are into lifting, anything from All Things Gym or Hook Grip. They focus on weightlifting, but it's fun to watch top athletes do their thing. You can also learn from their warm-up routine and assistance exercise.

https://www.youtube.com/watch?v=cv_EWWDV2O0

https://www.youtube.com/watch?v=YgyVhFnT-zY

My theory is Android is too difficult to maintain. There is a significant amount of work that has to be done to keep up with the latest version of Android especially if you are going to make heavy modifications to the functionality of the OS. That's why most aftermarket head units don't bother and you get out of date systems with security flaws. It is much better to build a system from scratch like Tesla and most other auto makers do from a support perspective. Android Auto is probably the best of both worlds for most people.

Hardware is the biggest challenge and what I assume you are asking about. My first approach was to get a double din computer case, which gives you an aftermarket look. The better option is to go to the junk yard and get a stock head unit and replace the internals. The problem here is finding an LCD that fits the dimensions. Another thing I've been thinking about is using a larger LCD that sticks out of the dash like the Tesla Model 3. Downside here is there is no space for physical buttons which I really like.

Great project. Offline mapping is a great feature addition. I'm working on a similar side project using C++ and Qt. I tinkered with Qt maps for a bit, but found it was sucking up too much of my time building a navigation app with all of the necessary features so I scrapped it. I will probably try to integrate an open source mapping app later on to make life easier.

So far, I got music streaming and voice calls working over bluetooth and I'm currently working on cleaning up the UI. I'm also considering upgrading my board to the i.MX8 which recently came out. Next I''m planning on adding an LTE modem, OTA updates and some kind of basic music app.

I do this with the Sony Xperia X. Updates are relatively frequent [1]. There are a few bugs with the AOSP version. For example, the phone doesn't come out of sleep when the alarm goes off. Otherwise, I'm very happy with it. Plus it's fun to hack the OS when I get time.

[1] https://developer.sony.com/develop/open-devices/latest-updat...

I recently switch to a Sony Xperia X and I'm running AOSP built from source. If you just need a browser and want to make phone calls this is an OK solution.

https://developer.sony.com/develop/open-devices/

Love the concept. No login, super simple to use and well defined use case. There are a bunch of obvious features you could add like a timer or the ability to edit a workout, but I appreciate that you decided to get people using it first. I need this kind of discipline. Congrats and good luck!

I just updated my Dell, but haven't restarted. Do we know how widespread the problem is and should I roll back the update?

Implementing this exact solution probably won't work for most people, but I found the idea of digital fasting a productive one. Try some less extreme variation of this like getting a dumb phone or switching to a paper magazine for your general interest reading for sometime. I found I built better habits offline that also translated online.