50 cubic metres out — and still counting correctly
My gas meter has two data sources: an accurate one days behind, and a current one with a wrong starting value. Only together are they worth anything.
Topic
Network and measurement
Radio, line, throughput. And what you measure it with without fooling yourself.
21 articles
Flatness was the proof — two lines, two wrong suspects
Two radio links, two months of measurement. In Kapfenberg the culprit was my own automation, in Merano the measuring tool itself.
Two identical buttons, and "long" means different things
One button at the door, one in the bedroom. Both identical, both with three gestures — and the most important gesture does something entirely different on each.
For thirteen hours the shut-off hung on the cloud
A network outage, two new addresses — and the local path to both water valves was dead. Why fixed addresses matter most when you work locally.
What does a flat cool towards? Not the outside air
Seven hours with no heat in the circuit, and the question of how far to preheat. The answer hung on a figure I had assumed wrongly at first.
What a radiator thermostat measures is not your room
Three homes, three ways to a radiator: tado over HomeKit, Shelly over Zigbee, and once no valve at all. What each gives you — and what none of them can do.
Three rooms cooled down — and nobody had a window open
A home-built detector spotted ventilation in an empty flat. The interpretation was wrong, and the real reason called a whole measurement series into question.
The weaker mast was the better one
After turning the antenna, reception fell from −71 to −87 dBm and I advised turning it back. Four days later throughput was four times as high.
The regulator's client, self-built — and then there were three
A second measuring method alongside Ookla: the regulator’s own client, packed into a home-built add-on. And three instruments that falsified each other.
Bandwidth was never the interesting number
The bundled integration was off by a factor of four. The Ookla CLI showed the real finding — and the antenna web interface ended the search for a cause.
The power nets out, the energy does not
The house meter measures three phases. It nets the power against itself but adds the energy up — which makes its counters useless for the dashboard.
Measure fast, set slow
The solar battery offers nothing locally. The trigger arrives instantly from the house, the action travels halfway round the internet — that decides the design.
A few drops, and my phone speaks up
A leak sensor under 20 euros passed a real water test in my Vienna flat: instant alert, all-clear after 30 seconds, battery warning included.
Two masters on the same light
The Hue bridge automates by itself, even when Home Assistant is off. Use the same sensor twice and you will later wonder why the light goes out on its own.
First 36 devices, then 15 — and nothing had happened
One network scan, two results, one false alarm. Why ping is the wrong measure and the router knows more than any sweep.
Kapfenberg was standing in one day
The third installation was the fastest — not because I had got better, but because the first two were written down. Plus one measurement with no occasion.
One convenience feature cost me nine devices
A camera would not join the Wi-Fi, and in the garden the connection dropped. Same cause — and after switching it off, nine more devices were reachable.
35 minutes of cooling, zero degrees colder — the proof run
The air conditioner ran and did not cool. "Cools badly" is not a finding. How a complaint became a measurement series the engineer confirmed.
The current clamp sat differently from the plan
One meter in the distribution box, two clamps — and the assignment was swapped. A lamp proved it, its own reading only 1.2 watts away.
Six valves move house — and the radio network improved
The radiator heads spoke Bluetooth through two gateways. The same hardware can do Zigbee — and after removing the gateways the weakest link got better.
Merano was the first — with nobody to look things up in
The first of the three installations. Two things came out of it that saved time later — one of them was a quotation mark.