Ramblings of Mads Chr. Olesen
Modern TVs are very poorly suited for kids. They require using complicated remotes or mobile phones, and navigating apps that continually try to lure you into watching something else than you intended to. The usual scenario ends up with the kid feeling disempowered and asking an adult to put something on. That something ends up [ ]
As I ve written about previously I have had the Olimex A20-OLinuXino-LIME2 in service for quite some time. But one thing that I ve been curious about is why it s only available with 1GB of RAM, when the A20 chip itself can support up to 2GB? Could it be upgraded to 2GB RAM by a simple swap [ ]
This is a non-rational quest to make a cheap chinese LED lamp safe to use.
Der findes rigtig meget åbent data om det danske energi system hos Energi Data Service, f.x. spot prisen på elektricitet og CO2 prognoser per kWh. Det er dog overordentligt svært at finde den samlede pris man betaler som forbruger per kWh, pga. det uigennemskuelige datasæt over tariffer og priser. I frustration kom udbruddet: Giv mig [ ]
I had a need for an extra-extra long multi-cutter blade, so we made one in Hal9k. Until proven otherwise, we hereby claim it to be the world s longest, at about 30 cm from rotation point to the cutting edge. Converting Starlock-MAX to Starlock-Plus Initially I thought I could get away with just a 80mm long [ ]
Denne badeværelseslampe er udgået af produktion, og pga. monteringen og at man ofte har mere end én er det noget træls at skulle udskifte det giver ihvertfald en del skrot uden grund. Heldigvis er konstruktionen super simpel: det er udelukkende en LED driver (230V AC til 24V DC) og en LED. Lad os starte [ ]
First part of this series is here, covering the reverse engineering of the DRTV Chromecast App. I wanted the physical appearance to be extremely minimalistic, with slight references to various cubes from videogames. Because it is a remote control, it of course has to be wireless and battery-powered. The box is lasercut from 6 mm [ ]
I want to build a physical giant red button, that when pressed instantly starts a children s TV-show, in my case Fantus on DRTV using a Chromecast. The first part of the build is figuring out how to remotely start a specific video on a Chromecast. Initially I thought this would be pretty simple to do [ ]
DIY mounting and creation of solid wood shelves in an alcove with no visible mounting hardware.
The Wemos D1 Mini is an ESP8266 based prototyping board with WiFi connectivity and countless applications. It becomes even more useful in battery-powered applications, where with the proper setup, it can run low-powered for months at a time or only hours if done incorrectly. This is the quick and dirty guide to running a [ ]
4 years ago I posted a 4 year review of the Olimex LIME2. It seems that the lifetime of power supplies is approximately 4 years as now another power supply died, and this time also the SD-card was expiring. The LIME2 lives on however! It was a bit hard to notice, because the battery pack [ ]
Som med så mange andre huse fulgte der en Grundfos Alpha 2 cirkulationspumpe med da vi købte et hus. Den pumpede og pumpede, indtil den var blevet 13 år gammel: så begyndte den at flimre når den skulle starte op. Det er jo som sådan en rimelig hæderlig levetid, men også lidt mistænkeligt at det [ ]
Vi har en Aduro 1-2 brændeovn med Aduro-tronic, som vi generelt er rigtig glade for. Den har nu været i drift i 5 år, og har haft omkring 4500 optændinger. Generelt er designet rigtig fornuftigt, og med Aduro-tronic og Smart Response er det rigtig nemt at fyre korrekt. Den eneste anke må være at vi [ ]
I have a Philips Hue gateway at home that is connected to a number of Philips Hue lights, as well as some IKEA trådfri light bulbs, and a couple of OSRAM Lightify light strips. Most of the time the network works quite well, but some of the time a few of the lights become unreachable. [ ]
Vi har en fin moderne brændeovn derhjemme (en Aduro 1-2), som vi bruger ret intensivt til opvarmning af vores gamle stuehus. Et meget relevant spørgsmål er derfor: hvor meget bidrager sådan en moderne brændeovn til partikelforureningen i vores stue? Partikelforurening er små partikler af støv og sod, der bl.a. fremkommer ved afbrænding af fossile brændsler, [ ]
This is the considerations I did when building 1S80P 18650 battery packs, for a DIY powerwall. My design will go for 14 of these packs in series, for a nominal 48V system. I wanted a design that was: Very hard to short circuit, individual cell fuses, and generally as safe as possible Mechanically stable Balanced [ ]
Last week my A20-OLinuXino-LIME2 one board Linux computer quit working, with a power supply issue. I looked up when it was purchased, and realised it had been in 24/7 service for almost 4 years. I guess that is a good excuse to do a little review. It even turned out that it the board was fine, but the AC-DC [ ]
Vores Duka Passad 30 ventilator var begyndt at køre noget uregelmæssigt. Ventilatoren er ellers ret smart styret af fugtighed og IR-bevægelse, men vi bruger den kun fugtighedsstyret. Den var imidlertid begyndt ikke at kunne starte ordentligt: den reagerede fint på fugt, men motoren stoppede efter få sekunder, for straks derefter at starte igen. Der var [ ]
Some time ago we bought a nice used Ford 3000 tractor (3 cylinder diesel, Chief frontloader). It needed some work, and one of the items was a new wiring harness. After replacing all the wiring everything seemed to work fine, until one day all the instruments just died; this being a mechanical beast everything else kept [ ]
I have a fancy thermometer for my wood stove namely an Aduro Smart Response. The accompanying Android app basically shows a temperature graph, with guidelines as to whether the burning is optimal and when put in more wood. I have generally been content with the app: it is quite slow, but generally helps in more optimal burning. Recently however, the Android [ ]
I mit home-monitoring setup har jeg en AC-DC strømforsyning der laver DC-strøm og lader UPS-batterierne. Denne spænding overvåger jeg, som beskrevet i sidste blogindlæg. Grafen set for en typisk dag ser ud som ovenover. Der er en tydelig stigning i spændingen om morgenen og et tydeligt fald sidst på eftermiddagen. Det korrelerer forbavsende godt med hvornår [ ]
For my home-monitoring setup I would like an Arduino to measure the supply voltage it is getting from a DC battery UPS (Uninteruptible Power Supply). Unfortunately (actually by design, but that s another story), the power supply is 24V, which means it will put out anywhere from 21.3V-29.8V (according to the manufacturer), which is far too much [ ]
I have a iRobot Roomba 500-series vacuum cleaner robot, but without any remote, or command center or anything; alas, I have to push a button everytime I want the cleaning revolution to start 🙁 But no more! It turns out the Roomba can be programmed, quite easily, to schedule automatically, and all you need is: [ ]
UPDATE: The drivers were temporarily unavailable; they seem to be up again, at least on the Brother US site: http://support.brother.com/g/b/downloadlist.aspx?c=us lang=en prod=ds620_all os=128 I recently bought a Brother DS-620 document scanner that supposedly had support for Linux. It turns out it did, but only after a few quirks. I installed the official Linux drivers, and tried to scan [ ]
The scenario is: almost finished migrating from an old server to a new server. Only a few steps remain, namely change DNS to point to new server wipe disks on old server Done in this order, one might be unlucky that ssh ing in to wipe the disks lands you on the new server. If you [ ]
We all know the situation: We want to disassemble the most awesome pre-compiled object file, with accompanying sources, using objdump and we would like to view the assembly and C-code interleaved, so we use -S. Unfortunately, objdump fails to find the sources, and we are sad 🙁 How does objdump look for the sources? Normally [ ]
Som de fleste ved har nogle danske internet-udbydere spærret for adgangen til The Pirate Bay, bl.a. TDC. Dermed er det også blevet gjort umuligt at følge med i den nærtstående retssag mod nogle af folkene bag The Pirate Bay, hvor nyheder set fra deres synspunkt bliver publiceret på trial.thepiratebay.org. Dette synes jeg er helt uholdbart [ ]
So, I just installed WordPress, because I was starting to have a too long mental list of things that I considered blog-able . My current estimate of what I will be blogging about is: Sysadmin ing on a tight budget, Ubuntu Linux, MultiADM, various happenings in the Open Source world, and probably a bit about my everyday [ ]