Intro I wanted to detect my Siedle doorbell press using an ESP32 so I could expose it to Home Assistant. At first glance this sounds trivial—until you actually put a multimeter on the Siedle line. Siedle’s 1+n system is partially documented here: Systemhandbuch 1+n-Technik (2019) On my installation, the doorbell line sits at ~18 V DC when idle and rises to ~22 V DC when the button is pressed. There is no clean contact closure, and the line is clearly current-limited.

Ama-Drainer 301C Pump: A Surprisingly Simple Fix My Ama-Drainer 301C pump is installed in a KSB Box Mini—probably the kit your plumber installs for washing machines or small sinks that sit below the household waste line. Normally, you’d think this thing has an easy life… until it doesn’t. After my sump overflowed three times, I had cleaned the pump it worked after a good clean everytime, I finally called the plumber in the hope to use my building warranty to have it replaced.

Hacking the Pentair Jung Pumpen AGR device My house came with a strange little device called a Pentair Jung Pumpen AGR. Honestly, it might be the most overpriced gadget I’ve ever seen — essentially a passthrough plug with a small leak sensor that triggers a loud alarm. There’s no configuration, no smart features, and it’s only IP20 rated. Yet somehow, this thing sells for over €300(!). I’d never paid much attention to it — until recently, when a small leak (thankfully no real damage) set it off.

Modern Intel NICs have both an updatable bootloader and firmware (NVM). Updating this can both unlock new features in OEM cards and fix various issues. If your NIC is on a motherboard or non Intel reference design you may get NVM updates via BIOS and/or a special firmware package from the vendor but likely not. This trick probably only works for cards that are based on or very close to the Intel reference design.

CAKE (Common Applications Kept Enhanced) or tc-cake is a relatively simple way of setting up AQM (Active Queue Management) on a home network. What I find quite different about cake than other such protocols is that a clear goal of this is to make it relatively easy to setup for ’normal’ people. The main reason to setup cake for me on my home network was to try reduce bufferbloat. Which is essentially a fancy term for latency increasing when networks become congested due to packets being queued sequentially.