2021-06-07 Wireless enviromental monitoring with zigbee 1 week ago
Since January 2008 I measure temperatures and other environmental data in and around the house with 1-wire sensors and adaptors. These work fine but need wires between the sensors and that isn't ideal for quick spot measurements. So I looked into other options recently, and found affordable zigbee temperature/air pressure/humidity sensors. And an USB zigbee interface which works with linux and with a lot of the available application software. Because the next problem is going sensor - zigbee network - zigbee usb interface - some magic - database of measurements. Because I see myself wanting long series of measurements from a number of places in the house and testing without breaking those series I ordered two USB zigbee interfaces and eight environmental sensors. I guess I want production and development enviromental monitoring.
The zigbee stick is not the cheapest solution but it is documented to work with zigbee2mqtt and buying one supports work on that software.
- Zigbee interface: zzh! CC2652R Multiprotocol RF Stick (tindie)
- Sensors: Xiaomi Aquara smart home sensor air pressure temperature humidity (aliexpress)
2021-03-27 I bought a secondhand morse paddle and made a video about it 2 months ago
For a while I had a notification set for someone selling a morse paddle. Finally one came along at a reasonable price so I bought it. And.. I mentioned this detail to some people at work. Who had an idea of what a morse key is, but didn't know about morse paddles. So with my big mouth I said "I'll make a video about it". This was triggered by the fact that I recently learned about OpenShot non-linear video editor which is available for Linux too. So I created a video. And found out making a video of 30 seconds is a lot more work than 30 seconds. I watched some tutorial videos about OpenShot first and thought about what I wanted to show. I haven't added spoken comments because I didn't feel like doing those too. The video isn't great, I can see several beginner mistakes. But I get the point across of what a paddle does. There is a continuity problem because I used sunlight. Which isn't very constant. And I made several clips because I didn't think I would get everything I wanted to show right. But now there are changes in light and a bit in camera angle, even with using a tripod. And our neighbours were busy hammering indoors, so that can be heard too.
2021-02-15 Snow over the Netherlands satellite image 4 months ago
In the weekend of 6 and 7 February 2021 the Netherlands got covered in snow and temperatures dropped to -10 degrees Celcius. In the week after that weekend temperatures stayed low and clear skies made for nice weather for outdoor skating and other wintersports. I was reminded of being on wintersport holiday. I just had to look up the available images from the NASA Global Imagery Browse Services (GIBS) and found a great image from 13 February 2021. Click for more pixels!
Satellite image of the Netherlands 2021-02-13 with snow cover.
I acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Observing System Data and Information System (EOSDIS).
2021-01-28 Found on YouTube: Cruising The Cut 4 months ago
A while ago the YouTube suggestion algorithm came up with a video about a TV journalist / cameraperson who decided to live and work full-time on a narrowboat in the canals of England. The suggested video: TV Journalist Quits His Job to Live on a Tiny House Boat & Cruise UK Canals Full-Time. I guess the suggestion was in relation to some videos I watched about people with expedition vehicles. After that video I checked out the YouTube channel mentioned in the video: Cruising the Cut and I got addicted. By now I have watched more than two-thirds of the videos in the channel. David Johns describes the first steps in buying the boat, getting the boat ready to live on and the journeys along the canal network in England. The exact measures of the narrowboat are to make it fit in the canals that were dug in England as the first way to move goods when the industrial revolution allowed centralized production. The boats are 2.08 meter (6 feet 10 inches) wide to fit in all the canals and locks. The canals were dug by hand, so they are no wider and deeper than needed to transport goods. I did ask David about the term 'the Cut' because I couldn't find a good explanation for it. It is the term for the canal, because the canals were cut out of the land by hand. For my Dutch readers who wonder about canals in a not completely flat landscape: canals in England have lots of locks, tunnels and aqueducts to deal with those. Somehow this idea of a moveable home is nice to me. At the same time I am not a person for living on the water, and with all the plans for long cycling tours I still want to return to a nice home with all the comforts. One note: I do notice that David Johns comes from a background in television. Great quality video. And yes, I am fully aware that takes a lot of editing.
2020-08-23 Getting work done on the Camp Wireless rewrite 9 months ago
In the last few weeks I had actual time to work on the planned rewrite of Camp Wireless in perl. I rewrote it in perl and redid a small part of the CSS to use the CSS grid model to optimize Camp Wireless based on screen size. In the coming days I will create an 'acceptance' version of the site using the production version of the database, to iron out the last errors. I still need to finish the correct 404 generation from within mod_perl scripts, advertising and some specific cases. And it's a good idea to run a website security scan on my work. The look and feel hasn't changed a lot. I decided to present the same information in the same order and maintain most of the screenlayout.
2020-06-28 Future cycling goals (2) 11 months ago
As I mentioned before I have some future cycling goals which include some form of long-distance cycling journey, with serious influences from the book Computing Across America. Naturally amateur radio will play a part in such a cycling journey, just as Steven K. Roberts had on his trips. Via the german amateur radio club DARC I found this bit in the "Deutschland-Rundspruch 24/2020":DK3JB erreicht erstes Ziel auf seiner Funk-Fahrrad-Reise Hans-Gerhard Maiwald, DK3JB, hat nach mühsamer und beschwerlicher Fahrt, teilweise auch wegen schlechter Radwege, am 15. Juni gegen 21 Uhr sein erstes Ziel, Kappel im Hochschwarzwald, erreicht. Dabei legte er ohne E-Unterstützung 580 km mit seinem 40 kg schweren Radanhänger zurück. Dem 72-jährigen OM geht es gesundheitlich gut. Hans-Gerhard gelang es, den weitaus größten Teil der Strecke permanent mit seinem TH-D74 in APRS aufzuzeichnen. Dabei hat sich der 1200 g schwere 12 V/20-Ah-Lithium-Ionen-Akku sehr bewährt. DK3JB hat zahlreiche Verbindungen in FM und D-Star vom Fahrrad aus getätigt. Durch Ludwigshafen wurde er von mehreren Funkamateuren gelotst und seine Route mitverfolgt. Hans-Gerhard bleibt bis Sonntag in Kappel und radelt danach vorerst an den Bodensee weiter.And I found out more about the cycling tours between Siegen and Friedrichshafen in Germany via Funk-Fahrradtouren of DK3JB and it is very inspiring to me. There is also an article DK3JB wieder mit dem Fahrrad unterwegs nach Friedrichshafen - funkamateur.de with information about this tour in 2020 (all in German, which I can read but not really write). He has done this tour several years already, I found an article from the June 2008 trip: Mit Fahrrad, Zelft und FTM-10SE durch Süddeutschland (pdf). After having read a book about cycling through Europe with the Rhine as one possible route, this confirms my earlier thoughts. Combining recumbent cycling, amateur radio and a nice ride through Europe is the direction I'm thinking.
2020-05-12 Changing the CSS grid depending on screen size 1 year ago
A special feature I realized when working with the CSS grids is that I can change the order in which objects are displayed based on screen width. Or whether they appear at all on small screens. So now I'm working on stylesheets that change the grid to what works better on a mobile device. Which is what a lot of the visitors to Camp Wireless use! On a small screen I want the important content to come first. There is not enough space for the extras at the top, and a mobile visitor wants fast answers to the question "where can I find a campsite".
2020-05-06 I discovered the CSS grid model 1 year ago
In my todo-list is a rewrite of Camp Wireless to stop maintaining PHP and make it more mobile-device friendly. The reason to stop maintaining php is because I don't like it anymore which gives me a risk of having insecure code, which would be really bad for me. I'm rewriting it in Perl which isn't todays choice in web development either but it is what I can program good enough to avoid security errors. The reason to make it more mobile-device friendly is that over half of the visitors to the site are using mobile devices. They want to find a campsite while travelling with a smartphone or other mobile device. I was already using a media selector CSS, with variations for printer, I'm now looking at CSS grids which allows me to device the page into regions that move place depending on the available screensize. This makes separating content from page layout even easier.
2020-05-01 I'm not intimidated by morse anymore 1 year ago
Today I "chased" the special amateur radio call for the Bulgarian Saint of this month, LZ177GL. The Bulgarian Saints are a set of special amateur radio calls each month, organized in Bulgaria by Bulgarian Radio Club BLAGOVESTNIK LZ1KCP. The callsigns are in honour of saints from the orthodox church. LZ177GL was calling CQ at a rate of about 28 words per minute. My current rate is 12-13 words per minute, so that's quite a lot faster. But it doesn't intimidate me anymore, I can hear the callsign on a few repeats, I can hear when the return is with my full callsign and a 5NN (signal report) or a part of my callsign and a question mark. Or when the answer is for another station. And that's enough to make the contact with the absolute minimum information, exchanging callsigns and signal reports. When I'm convinced my callsign got across I send '5NN TU 73' to finish the contact. I also made some other contacts in morse because I could hear CQ calls and was able to decode them by ear together with some help from fldigi. So my conclusion is that morse isn't "intimidating" anymore. I can understand enough to get an idea what is going on and use it.
2019-11-16 Getting distracted by weird noises and listening to data from car tires 1 year agoItems with tag shiny before 2019-11-16
I was tuning across the 70cm amateur band and heard lots of weird noises around 433.92 MHz. Which is logical: that's the ISM band (industrial, scientific and medical) so lots of unlicensed low-power signals there.Read the rest of Getting distracted by weird noises and listening to data from car tires
That triggered me to update rtl_433 and see what I could receive. The answer after some searching how to build a running version: a lot. Including tire pressure monitoring sensors (TPMS) on a nearby car:time : 2019-11-16 15:33:25 model : Toyota type : TPMS id : fb8c8bf9 status : 128 pressure_PSI: 38.500 temperature_C: 6.000 mic : CRCThere is indeed a Toyota parked across the street. I see three different values for 'id' suggesting that three wheels are 'awake' and reporting tire pressure data about every two minutes. According to eavesdropping the wheels, a close look at TPMS signals the sensors should only activate when the car is going faster than 40 km/h or when a special LF signal is active.