Notebook Batteries don’t balance

TL;DR: Don’t trust the vendors. They only monitor the cells, they don’t balance them. Introduction It’s a less known fact that most notebooks don’t balance their cells. Maybe some do, but I haven’t found them yet. So I added an active balancer   Buy it here: What is this? This is not a regular

Evolution of Chinese Car Chargers

TL;DR: Chinese Engineering has surpassed Western Engineering [cmtoc_table_of_contents] Introduction I’ve shown some interest in Car Chargers in the past: Tuning a dual usb car charger Dual USB car charger update   Quick Charge But the time goes on and today we apparently need Quick Charge to surpass the measly 5V 500mA of the original USB

Teardown: SportDV Camera

TL;DR: Just buy big brand or open source cameras I ride a road bike in Germany, Cologne. And you probably know that 1% of drivers out there who are crazy and trying to work out their personal problems in traffic. Recently, someone opened his car-door intentionally when I was riding by. In the aftermath, the

Liquid thermal paste in laptop

TL;DR: Don’t use it in portable things as it cracks My laptop has become loud and slow over the years. This came from permanent 90°C CPU temperature and thermal throttling. From my experience, the manufacturer never uses the correct of thermal paste, so I opened my laptop up and applied Coollaboratory liquid pro thermal paste.

Connect Batteries easily

TL;DR: Use magnets to connect batteries Most Batteries contain Iron or Nickel. Just use a magnet to  connect the battery. On the other side you can use one of those cheap copper-clad cables from china or alligator clips Bonus: The magnets automatically disconnect if they reach ~90°C in case of a short circuit.

Lowside current measuring gone wrong

TL;DR: Always take into account the ground bounce. Introduction I’m developing a software controlled Switched Mode Power Supply (SMPS). For this I need to measure current at ~250kHz. This is a recollection of the false assumptions and mistakes I made. The circuit I’ve decided to measure the current lowside as it seemed easier when I

Blackmagic probe

TL;DR: Flash new software to a cheap STLink v2 clone to get an integrated gdb Essentially, I just followed the the instructions in their wiki. I still had some problems guessing the pinout and documented my progress. Hardware: To program the controller with new software you need a second programmer. I used another STLink clone

Dual USB car charger update

TL;DR: Chinese USB adapters work out of the box


I’ve bought a new car charger because the old one was too big. The new one is made from aluminum to dissipate the heat better and doesn’t waste that much space.

It’s 2.26 USD including shipping on aliexpress. I’ve expected the electronics to be garbage as the one before but i was pleasantly surprised:


A double sided PCB with plenty of vias and a good layout. I’ve checked the switching node with my oscilloscope (no screenshot) and everything is rock solid and no ringing. I couldn’t have done it better myself.

The components are good as well:

Working with Lua on an ESP8266

TLDR; use luatool to upload scripts Lua is a scripting language which has been ported to the ESP8266. After flashing the latest firmware you can connect to the module using screen /dev/ttyUSB0 You probably want to save your entered code over a restart. Nodemcu offers a whole file api which tells you how to manipulate