Reddit:Electronics

Just wanted to share with you this gem that I have found on aliexpress:
Buck converter Mini560.
According to the seller this are the specs:
5.5–20V input to fixed outputs of 3.3V, 5V, 9V, or 12V depending on the version.
5A max, >3A with cooling.
99% efficiency

Be aware that there are different modules out there and not all of them perform well, so if you get lucky you'll get an awesome dc-dc converter, but it seems that is easy that you'll get the bad ones.
The photo belongs to the actual module that I have tested.

This little thing has capabilities beyond belief, I have thrown in the trash bin all my old and bulky buck converters as they cannot do half what this small buck converter can do in such small footprint.

I have tested it at 10V input and 5V output.
It has maintained the output voltage without issues in any case.
Under 5A always at ~100mVpp ripple, at 6 and 7 amps the ripple has stood below 300mVpp.

I have tested it naked at 28C room temperature, without cooling, with 2 small heatsinks for the chip and the inductor (even though the inductor does not heat up that much), and with the heatsinks plus a fan. I have pushed the module well beyond what the seller recommends.
Every test has been measured after 10 minutes ON.

These are the results:

I have not tried going further, just tested it extensively to know how can I push it safely.
So I would not use it over 5A, just to be clear.

So yeah, one of the best modules I have gotten my hands on.

Set your DMM to "Diode test" Mode. Identify the transistor`s three terminals (let BC547 i.e., base, collector, and emitter) by using its part number and datasheet. Connect red probe to base and black probe to collector/emitter, you get ~0.6-0.7 V (result forward bias). This means an NPN transistor is good. Reverse the polarity gives us no reading (i.e., OL). Otherwise, NPN transistor is faulty.

Transistors: 2N2222A.

From the research Ive done, they were used as diodes to rectify up to 150 kV with a rating of up to 1A. 24" long by 6" diameter. Thinking of building a base/stand and using LEDs to illuminate them as a lamp/display piece! Used ChatGPT to show what they might look like once finished!

I pre-planned a customizable keyboard matrix into my cyberdeck without actually designing the keyboard itself yet, so I could add one later. This is basically a rough version.

I also thought about splitting it into two halves and putting one left and one right of the display. My fallback is still just a USB dongle with a wireless keyboard, but I wanted to try this out and see how it feels.

The layout is based on the old Nokia E7-00.

I still like old-school self-etching with the photo-positive method for stuff like this. You can make a board, notice something stupid, fix it and do another one the same day.

It’s far from perfect, but that wasn’t really the point. I mainly wanted to see how the spacing feels when actually typing on it. I already have another idea that would make it lower profile and simpler, but I really like the crisp click sound of these switches compared to the lower-profile ones, so I wanted to give them a shot.

The black vertical bars keep the keycaps in place without getting in the way when you press the keys.

Not a single via was required here, and ghosting is prevented with simple diodes. The board also has a basic keyboard-matrix IC (TCA8418) on it. Usually it would be cleaner to expose I2C and put the IC directly on the keyboard imo, but I have some other keys on the main board as well, and the cable mess is still manageable this way.

Won’t win a beauty contest, but it works. Sometimes just building something and actually using it is necessary imo before optimizing anything.

This is my project that I’ve been working on for the last two weeks. It’s called Kira04 AIRNODE.
I currently 3D print in my small bedroom, and I have three printers running simultaneously, sometimes almost 24/7. I started getting worried about the VOCs they release, as well as the amount of heat they generate, so I came up with this project.
Kira04 AIRNODE is basically a bundle of sensor modules that connects directly to the ventilation system I installed in my window. It helps me monitor and keep the temperature, humidity, and VOC levels in check while my printers are running.
And yes, I know the wiring and soldering are pretty horrible 😅. There are wires everywhere right now. I actually tried making a custom PCB for it using my CNC mill a few times, but unfortunately both attempts failed pretty tragically 😂. At that point, I just wanted to get the project working, so I decided to finish it quickly with the current wiring.
I’d love to hear any feedback or suggestions you have for improving it.
I’m also trying to decide what to do with the project next: Should I open-source Kira04 AIRNODE, or do you think this could potentially become an actual product?

opened up a broken controller to see if I could use the D-PAD in one of my project. Totally separate from the main board with 6 pin inputs. It‘s beautiful.

7 years ago I designed a single board computer PCB. That was for a retrogaming console. It included a A20 SoC, ram, battery management system, Ethernet, HDMI, emmc, wifi and so on.
I did everything on my own. Those were some good times. I loved rooting that PCB.

Now I appreciate that the hardware industry didn't have an "open source" culture around it before AI or else we would be doomed.

I found productivity apps were just another distraction for me when I went to study, so using an ATTiny44, I built myself a productivity timer with custom analog dials. Also built a custom plywood case for it!

It works 😁

Some buttons on my SpaceMouse stopped working. Thought it would be a quick fix. Found out it is membrane after taking it apart(see my previous post).

I've always hated those stiff buttons since I got this device, so I decided to make my own.

The switches I'm using are 6.2*6.2*3.5mm with 0.7N operating force. I've also added some diodes to prevent ghosting keys, although probably no one would ever press multiple keys simultaneously on such a device.

The keycaps are hollow at the center, some metal stickers are used to make the contact area flat.

Working in a power electronics lab has exposed me to some of the most ridiculously oversized passive components out there. Sometimes it feels like I’m in those early electrical experiment demonstrations in the 18th-19th century with how big the parts can get. Anyone else work around this sort of gear?