Devices: PCB, OpenCV/RasPi and NVIDIA Jetson Nano

• A beginner tries PCB assembly

  I wrote last year about my experience with making my first PCB using JLCPCB. I’ve now got 5 of the boards in production around my house, and another couple assembled on my desk for testing. I also did a much simpler board to mount a GPS module on my MapleBoard - basically just with a suitable DIP connector and mount point for the GPS module. At that point I ended up having to pay for shipping; not being in a hurry I went for the cheapest option which mean the total process took 2 weeks from order until it arrived. Still not bad for under $8! Just before Christmas I discovered that JLCPCB had expanded their SMT assembly option to beyond the Chinese market, and were offering coupons off (but even without that had much, much lower assembly/setup fees than anywhere else I’d seen). Despite being part of LCSC the parts library can be a bit limited (partly it seems there’s nothing complex to assemble such as connectors), with a set of “basic” components without setup fee and then “extended” options which have a $3 setup fee (because they’re not permanently loaded, AIUI).

• Digitizing a analog water meter

  Sadly, my meter is really dirt under the glass and i couldn’t manage to clean it. This will cause problems down the road. The initial idea was easy, add a webcam on top of the meter and read the number on the upper half it. But I soon realized that the project won’t be that simple. The number shows only the use of 1m^3 (1000 liters), this means that I would have a change only every couple of days, which is useless and boring. So, I had to read the analog gauges, which show the fraction in 0.0001, 0.001, 0.01 and 0.1 m^3. This discovery blocked me, and I was like “this is way to complicated”. I have no idea how I found or what reminded me of OpenCV, but that was the solution. OpenCV is an awesome tool for computer vision, it has many features like Facial recognition, Gesture recognition … and also shape recognition. What’s a analog gauge? It’s just a circle with an triangular arrow indicating the value.

• NVIDIA Jetson Nano Developer Kit-B01 Gets an Extra Camera Connector

  Launched in March 2019, NVIDIA Jetson Nano developer kit offered an AI development platform for an affordable $99.

today's howtos

• Windscribe VPN on openSUSE

  With all the talk of VPN (Virtual Private Network) services to keep you safe and my general lack of interest in the subject, I was talking to Eric Adams, my co-host on the DLN Xtend podcast about the subject. He was telling me that he was hesitant to recommend any service so he gave me some option to try out. The one I chose, after doing a little reading was Windscribe. I am new to the VPN game so I want to be careful in saying, I am recommending this as the perfect solution but rather demonstrating how I set it up and how I am using it on my openSUSE Tumbleweed system. Much in the same way Eric informed me about it.

• How to Install Minecraft on Ubuntu 18.04

• How to Remove Top Bar Application Menu in Ubuntu 19.10, 18.04

• How to add podcasts to a mobile device with Linux

• How to transfer a file from a remote computer to a local machine on Linux/Ubuntu

• How to Make Linux Mint Look Like Windows 7

XMPP - Fun with Clients

As I already wrote in my last blog post there's much development in XMPP, not only on the server side, but also on the client side. It's surely not exaggerated to say that Conversations on Android is the de-facto standard client-wise. So, if you have an Android phone, that's the client you want to try&use. As I don't have Android, I can't comment on it. The situation on Linux is good as well: there are such clients as Gajim, which is an old player in the "market" and is available on other platforms as well, but there is with Dino a new/modern client as well that you may want to try out. The situation for macOS and iOS users are not that good as for Windows, Linux or Android users. But in the end all clients have their pro and cons... I'll try to summarize a few clients on Linux, macOS and iOS...

Linux disk resizing on Chromebooks pushed back to Chrome OS 81

The good news is that plans have been in the works since March of last year to allow you to reclaim some of that space by shrinking or resizing the Linux storage. The bad news is that after being pushed back twice since the feature is being put off again; this time until Chrome OS 81. You’d think this would be a relatively simple thing to implement but in reality, it’s not. That’s because the Chrome OS filesystem has evolved in the past year and due to expected support for a particular file type for older Linux kernels never worked out. I’d rather the Chromium team take their time for a well designed and implemented solution so as not to break any functionality. Plus there’s the challenge of having enough free storage to restore a container backup.