Posts

Home Assistant Brings the Watch Battery Down

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This one is quite interesting and I am yet to collect the hard evidence on what really happens. Long story short: Home Assistant can, behind the scenes, drain battery in a smart watch. It all leads back many months ago when I started seeing my Garmin fÄ“nix  watch dead every morning. I mean ALMOST every morning. Normally it can run for 1-2 weeks on a charge and suddenly every morning it was dead, despite being fully charged on the day before. I tried different things - software/firmware update of course, changing some parameters (but it had been working fine before) - no lasting improvement. Until this June (after having extensive travel period - US West Coast, twice to China and then Europe), when I realized that it did not lose the battery when I was away from home. I started thinking on what was so special at home that the watch, left for the night on my bedside table, was losing the charge completely. There was one idea that came to mind: Home Assistant. And to be precise: ...

Home Energy Revisited

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It has been almost 6 full months since (after long procrastination) I finally completed the home energy monitoring project . In short: Home Assistant + Circuit Setup energy meter based on ESPHome. Long story short: all has been working flawlessly. There have been multiple routine firmware updates (they are released ~monthly). To be honest I have not paid (almost) any attention to them. Luckily nothing got broken, but equally Home Assistant could be releasing one update per year. This is a side observation, but generally people are fed up with software updates. Even if they go flawlessly, there is always the risk of something getting broken. I've been hearing the same from our customers: you release too frequently (we used to every 6 months, but now there is the pressure to release at most once a year). Ove the 6 months I have learned quite a lot about my usage patterns. Daily hot bath is an energy hog, but I can easily run the boiler when the energy is least expensive (=middle of ...

China Manufacturing

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High speed trains in China are phenomenal. I could sit by the window for hours watching the passing landscape. They do not run on ground. They either soar high on concrete bridges and piers or pierce through tunnels. It is thousands of kilometers of piers and tunnels. And the landscape mostly flips from agricultural fields to endless seas of industrial buildings - factories. It is totally unlike anywhere else. When the train enters an industrial zone, there are thousands and thousands factories. It probably takes such a train ride to understand the hypothetical effort of moving manufacturing to the West. The factories form a unique and super efficient industrial supply chain. It is not about the iPhone. While a flagship symbol of Western dominance, we could do without iPhones. But probably we could not do without lights, linen, pots, just about every daily used item is made in China. And then there are basic components to make them: wires, bolts, glue, paint. And then the raw materials...

China: Getting Around (4)

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In this last part (so far) of the Getting Around in China mini-series I'd like to share tips on personal mapping and navigation software. Actually this is a one big tip. The Gauda / Amap mobile application. In different markets (app stores) it goes by different names, so search the app store for either Gauda or Amap. This is the go-to replacement for Google Maps or Apple Maps. While both Google and Apple work to some extent in China, their functionality is severely limited. They will not find you any public transport options and even basic driving / walking functions are limited. Also in several interesting areas Amap offers very interesting options not available in any app in the Western hemisphere. Driving in underground garages. I still need to explore the technical side of this, but the long story short is Amap can navigate in underground garage structures. Clearly no satellite reception there, so I suspect Bluetooth beacons may be at play. Nevertheless you will appreciate the ...

When Software Goes Down

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The terrifying crash of the Air India flight 171 in Ahmedabad has ignited a number of theories on the cause of the accident. The plane took off and went down immediately as it appeared to lose thrust in both engines. Today's aircraft are considered very safe. The key for the safety record is redundancy of all critical systems. Everything is doubled or tripled or quadrupled. From the probability theory perspective, multiplying the critical components vastly reduces the chance of a total failure, as the individual equipment unit failures are considered to be independent. That is mostly true for legacy / mechanical components. An engine blade failure in one engine does not cause the other engine to fail. Or a chance of two blades (one in each engine) failing at the same time is practically zero. But it turns out when software is involved, equipment failures can be fully synchronous. Which I believe is what happened in this accident. In the Boeing 787 Dreamliner, the fuel pumps are el...

China: Getting Around (3)

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In this third episode of the China: Getting Around mini series I'm going to share tips about long(er) distance travel in China. So far we have already covered passports, eSIM data in part 1 and translation apps, mobile payments, WeChat and DiDi in part 2 . Airlines. There is not much special about how airlines work in China. Buy tickets online, show up for check-in etc. There are some differences related to items allowed in a carry-on bag. For example foldable walking poles are not allowed. So are not multi-tools designed as so called "TSA-safe" (from my experience, they are not in Mexico either). As they say "a tool is a tool and tools are not allowed". Period. Cigarette lighters are prohibited too, and there is an interesting solution - you drop the lighter before security in a box and that box then goes to the security exit door where disembarking passengers can grab lighters.  Trains. High speed trains are what China is really famous for. The network is inc...

China: Getting Around (2)

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You have the passport and a phone with the internet on it. What is next? Translate. Unless you speak Mandarin, a language translator app in the next on the list. Language has been a barrier, but translator apps break through that barrier. Use the one you like. I use Google translate. It is prudent to download the languages for offline use. Once done you can either type or dictate (or have someone else dictate) or use camera for instant translation of signage or restaurant menus. The apps are not perfect (yet), but they do a really good job. On one of the past trips, for example, we were able to negotiate a set of medicines in a pharmacy. The pharmacist was asking many questions in Chinese, us answering in English, and ultimately the medicine worked very well. Payments. As I mentioned, China has its own preferred payment systems. Credit cards would not work in most cases. Maybe in higher end hotels. But the default means of payment is by presenting or scanning a QR code. The app I use m...