Since the creator’s site is unavailable and has been for some time, I’m hosting a mirror of a binary of the handy HexUploader. It was available through a third party. This is a small Mac app that allows uploading .hex files to a ATMega chip implementing the STK500 bootloader, e.g. Arduino’s. I used it to flash GRBL.

Since lots of people come looking for the Arduino Uno technical drawing, I decided to make a drawing with the main dimensions of the Wemos ESP32 as well. It’s probably the same as the D1 and other Lolin / Wemos modules. It’s based off the CAD-model by Ben Cooney on GrabCAD.

Since lots of people come looking for the Arduino Uno technical drawing, I decided to make a drawing with the main dimensions of the Arduino MKR1000 as well. It’s based off the CAD-model by Johannes Funk on GrabCAD.

Since lots of people come looking for the Arduino Uno technical drawing, I decided to make a drawing with the main dimensions of the Arduino Mega as well. It’s based off the CAD-model by Augustine Aelevanthara on GrabCAD.

For an electro-mechanical designer, motors are a key component. Being able to move stuff in the physical world at high speed and precision makes modern products feasible. For a long time brushed, DC Motors were the only viable option, sometimes coupled to a gearbox and or encoder. Lately, more and more products began using brushless motors which also means cheaply available overstock.

You can now buy a powerful and fast brushless motor, including controller and and encoder for precision feedback for about €5 including shipping(!).

I just had to try these out. Attached is the code for open-loop control. I might implement closed-loop some time in the future as well, so this becomes even more powerful and precise.

30th of April, there was a break-in at our house and several bikes were stolen; one of mine and the others from the neighbors.

Frame number: GZ60560592
VIN: XRGA0H57A6A000281

If this bike is offered for sale to you, please get in touch with me: https://www.krekr.nl/contact/

Op 30 april is er bij ons ingebroken en zijn er meerdere fietsen gestolen; één van mij en enkele van buren. Indien deze fiets u te koop wordt aangeboden, neem dan contact met mij op: https://www.krekr.nl/contact/

Dutch manufacturer Itho Daalderop seems to have an electronics reliability problem. I’ve now repaired 4 fans from the brand.

One common problem seems to be that the transformer on the PCB of the CVE “Centrale ventilatie eenheid” breaks. It is a very common part that can be had for about €5, e.g. at Reichelt.

The epoxy of the potting cracks. Maybe it gets too hot, maybe unfiltered spikes on the mains net cause this. Of course, these units run 24/7, but I’d advise anyone to add extra precautionary devices on any Itho appliances they might have.

Starting today, I’ll be posting teardowns of consumer electronics every month or so. These photos have been taken a long time ago, but are still relevant because most of the manufacturing technologies haven’t changed.

Resistive welds can clearly be seen, as well as an injection moulded Zamack frame. Lots of EMI gaskets and flexible circuit boards too. And a repair I made circa 2009.

I’ve has issues with my Sonos setup since installing it. It would sometimes disappear from the network, sometimes the app wouldn’t see the system etc. Today (after more than a year of disappointment) I was guided through an hour-long debugging session by the very helpful Jenny, which changed the following ASUS router settings from their defaults:

Advanced settings > LAN > IPTV > Enable multicast routing
Advanced settings > LAN > IPTV > Enable efficient multicast forwarding (IGMP Snooping)
Advanced settings > Wifi > Professional > Enable IGMP Snooping

Also, check if the firmware of the router and mesh nodes are up to date, and whether the Sonos app displays any other (old/concurrent) Wifi networks (otherwise the system might keep switching back and forth).

I created an integrated EAGLE library for the affordable 100V Infineon IRS10752 MOSFET Gate driver (the download from Infineon provides a package and schematic symbol, but not a ‘device’ with the right connections).