Adventures of a Tech, avonturen van een techneut

 I just received my second batch of PCB's from JLCPCB with components assembled in China. How good is it really, we will find out soon enough. Everything works fine. Need to wait on correct USB-C connector, UART works, no problems so far.

NOTE TO SELF: change DNS on TransIP VPS machines. Today I got an email from TransIP. Nameservers are changed.  Please update your virtual machine. Old info :  80.69.67.66, 80.69.67.67,  2a01:7c8:a::c53,  2a01:7c8:b::c53 New info is : 195.8.195.8 195.135.195.135 2a01:7c8:7000:195::8:195:8 2a01:7c8:7000:195::135:195:135 Ok, now I have to get into my machine and update this stuff. I used my normal SSH login to get a prompt.  (user oetelx can use sudo because this user is in admin group ) I checked if the new IP adresses actually are running a valid DNS server before assuming anything. oetelx@www:~$  dig @195.135.195.135 www.oetelaar.com ; <<>> DiG 9.11.3-1ubuntu1.13-Ubuntu <<>> @195.135.195.135 www.oetelaar.com ; (1 server found) ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 3218 ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 2, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDN...

DuoTank version of new TiMO tank monitor unit, approx 53x32x12 mm total size. The new version is the same size as a 9 Volt battery. As you can clearly see this latest one matches the DuoTank logo. (contact Duotank for purchase / implementation details) Screenshot of #ABI dashboard Timo Tank monitor, showing levels declining, speed and date. 2 early TiMO units on table, this version used a separate light source. Previous versions were reliable but fairly large. This one is still in operation. TiMO unit on tank, still operational on location. This is an early model. TiMO dashboard as used by customer, showing locations and online status/levels of all tanks. This data is pushed to brewery ERP system to automatically optimize route planning of tanker vehicles. Currently installed in 23 location in the Netherlands with 100% uptime. Find more content using hashtag : #oetelx

Good day to you all. I have just released this project I did in a day in 2016 under MIT license. It was a project to help someone quickly get a water dispensing system up and running for "Het Concertgebouw" a famous building in the Netherlands. The project was for a foundation "Join the Pipe" that tries to bring fresh drinking water to everyone in the world (Which is generally a positive thing). The code was written in plain C (using Clion IDE for typing the code) on a linux system for an AVR ATMEGA 328P which is inside the Controllino Mini. Hope you learn something from it. Link to Github project : https://github.com/edwin-oetelaar/join_the_pipe It all worked and was delivered in a few days. Some pictures tell more (maybe) Find more content with hashtag : #oetelx

Maxtor Shared Storage NAS 300 GB Summary of long adventure: TL;DR. ONE DISK IS NOT AN OPTION FOR A NAS - Audience : advanced users - linux skill required : yes - strong opinion : yes - frustration : yes It looks so nice in the picture : storing data on a NAS, not on the local system. You can access it from anywhere in the network, all is fine. Until.. The NAS breaks down and you forgot the backups.. I had this NAS for a long time (several years), somewhere safe in the house, in a dry and protected and cool place, nobody would be able to find it, a digital safe, connected to my local network. It seems a smart idea, but it really was not. Here is my summary of trouble to get my data back. 1) The NAS did not appear in my network anymore 2) Checked power supply, switches, cables 3) conclusion, NAS is bad 4) reboot, does not come online again 5) open it up, take out harddisk, how hard can it be? Right? I connected the disk to my machine with one of those PATA/...

Yesterday and some days before I did some experiments in testing the LoRa radio modules I have from microchip. The modules were connected to some laptops over USB serial. I wrote some python scripts to send data using the pyserial library. One laptop was sitting on a table indoors, no real antenna, just a piece of wire. The other laptop was outdoors, walking around, no real antenna, just a piece of wire. The spreading factor for LoRa was SF12, power was set to high. Further details available on request. (email me) This experiment was very successful, about 1 kilometer, good connection, no loss of data. In the picture above, Richard is holding the laptop and the RF module, we are about a kilometer away from TX and get perfect data, on the overpass above the A2 road. But when we got between a lot of buildings, the results were not that good. At 700 meter we lost connection. 500 meter was mostly fine. In Tilburg an experiment was done.. and 500 meter urban was not...

I got a DDS with a serial interface https://bitbucket.org/tweetand/udb120x/overview You can now control the device over a serial/USB port if you want. Use my code, original research.

Het heeft even geduurd voordat ik het snapte (en nu vind ik het nog een vreemd concept) maar ik heb ondertussen bitcoins. Ik heb uitgevogeld hoe je een wallet maakt, hoe je er geld op zet en nog wat details. Het lijkt ingewikkeld maar is dat dus helemaal niet. Ik gebruik Armory (https://bitcoinarmory.com/) dat samenwerkt met bitcoin-Qt (https://bitcoin.org/en/download) Via https://bitonic.nl/ en https://bitmymoney.com heb ik wat transacties gedaan en dat werkte vlekkeloos. Wat me vooral opviel was dat je ontzettend lang moet synchroniseren voordat je aan de slag kan, heb geduld, trek hier gerust een nachtje voor uit, daarna loopt het snel. Als je geld via Ideal overmaakt naar je bitcoin adres staat het er binnen een paar minuten op. My public wallet address is :  1DynDMhxWweJr6aoSZXUzenJMkSjaWHGxo  you can send donations there. Dus als u mij geld wil sturen mag dat op adres :  1DynDMhxWweJr6aoSZXUzenJMkSjaWHGxo Bij voorbaat dank, :-)

One of my other PC's started giving trouble. Random hangs and crashes, not normal behavior. The system runs Linux-Debian-7 so it should never crash ever. After the usual updates, rebuilding the video-driver (nvidia closed source driver) it still was not fixed, and since my wife needs the PC for book-keeping I was ordered to fix the problem (or get a new PC). Replace the Cap (with a lower ESR, higher voltage and bigger capacitance I had in stock) This is becoming a common weekend activity. :-) Problem solved. Saved myself a lot of cash again not buying a new PC.

A few days someone gave me a TS 201 RAID NAS made by Qnap to fix. http://www.qnap.com/useng/?sn=862&c=1697&sc=1698&t=1701&n=6731 It was very bad, the power light did not come on, it just pulsed a bit. The external power supply was broken, the capacitors 16V/1000uF swollen up. 12 Volt 5 Amps standard PSU, I had a spare so that was easily fixed. Trouble was not over, the device did not work. It beeped, lights were blinking, ugly noise from disk. Connecting to NAS did not go easily, I found the IP address by using NMAP (I assumed it was using DHCP) $ nmap -sP 192.168.1.0/24 .. some known machines.. and Nmap scan report for 192.168.1.217 Host is up (0.00034s latency). Connect to the thing using a web browser did not work. type in :http://192.168.1.217/ click 'administration' That redirected to a webserver on port 6000 why? New rules in Chrome and Firefox, blocking ports including 6000. I got something like this very descriptive message : ...

I have today finally fixed the issues with my Raspberry-PI. If I have these issues everybody must be having them, USB problems! After spending the whole day measuring and tinkering it seems to work. There are some serious design-flaws with the board, to say the least. UPDATE: it is not completely fixed, after a few hundred open/close calls on a sound card (alsa on USB) the problem still happens, the USB locks up. I will not use a R-Pi again. What a piece of marketing hype it is.  One of the thing I need the R-Pi to do is run of 12 Volts, not a 5 volt USB connector. So I added a DC/DC converter (which also insulates the ground connection, which is always good when doing audio or mounting stuff in a car). It appeared to work fine but the usb-audio-card kept failing, after opening it 20 times or so. I also have a Pi-Face board connected so that complicated the situation. When it ran it ran OK, but sometimes it just did not work. I do not like these intermittent problems, s...

The Raspberry PI or R-pi from  http://www.raspberrypi.org/  is well known these days. It is not an accident that I have one, I have been doing Linux stuff since 1991, and professionally since 1996 I can not skip over these developments, have to keep up with the new kids. :-) Times have changed, hardware has become very affordable, everybody knows the Arduino , Raspberry Pi and Beagle-Bone-Black (BBB). Not everybody knows the stuff that  http://www.acmesystems.it/  aka Acme-Systems and  https://github.com/OLIMEX/OLINUXINO  aka  Olimex make, so I will endorse them here. Since I am an engineer I expect to connect switches and relays to the boards and some documentation with products, not so with the " PiFace Digital " board, it comes without serious documentation, not a even the schematic. All links on their blog point nowhere. People asked them many times, yet nowhere is the schematic to be found. I finally found some info after hours of googl...

I have done many things already, but recently someone asked me to find a way to automatically test and report findings on very large Diesel generators. The project involves building a portable (with a crane) setup for testing the performance of generators upto a power of about one MegaWatt. (MW) For me that is a lot of power.  The test involves increasing the power output stepwise and measuring the response of a generator, including Current, Voltage, Frequency, Power factor and Temperature.  I have taken a picture of the resistor array we apply to consume this much power from the generator. The resistor array has forced air through it, and can take about 3 x 1500 Amps at 400 Volts. The plan for now : Laptop with RS485/Modbus to the control- and measurement- equipment. Possibly linux as the OS to prevent tinkering, security, driver and update issues. update 2013/6/13 : I already wrote python program to control the measurement module ( Diris A10 over modbus RS48...

Program to control Relay-Board via USB on BitBucket https://bitbucket.org/oetelaar/ch341a-relay-board I wrote a new small clean program to control this board from Linux. No need for any 'drivers' and other stuff, just type 'make' and it works.