Author: Martin

Perhaps some of you still remember the days when GSM base stations were spaced far apart and it was fun to search for them by using the timing advance information shown in the hidden monitoring tool of your GSM phone? Well, perhaps not but this method came in handy again when two people asked me within a few days of each other how they could locate the base station from which their hybrid DSL/LTE home gateway was served so they could perhaps improve their data rate by re-locating their LTE modem.

Continue reading Using the GSM Timing Advance to Find an LTE Base Station

So how exactly did we end up with graphical user interfaces, touch screens and shell windows? Apart from improving my understanding of how a CPU really works, understanding the evolution of how users interact with a computer with a keyboard and screen, or a touch sensitive screen on mobile devices, and how this maps into hardware is a favorite past time of mine. So how did we end up with pixels? Continue reading From Teletype to Touchscreen

Just shortly before I got my first computer back in the mid-1980s, Steven Levy wrote “Hackers”. The book has become so famous over the years that there’s quite a long entry about it on Wikipedia. I’m not sure why I haven’t picked it up earlier as the story of the book ends just by the time I got started back then and thus would have given me a good idea of why I found things in place as they were.

Continue reading Book Review – Hackers by Steven Levy

It’s summer time and while most people go on vacation it’s also the time of summer camps and hacker conferences. Last weekend I went to Froscon in Sankt Augustin in Germany for the third time. Close to Cologne and Bonn and not as over-run as Congress in December it’s also a great place to discover new things and get inspired. Back in 2015, for example, I discovered Conversations at the conference, a great XMPP messaging app that I’ve been using ever since. I like to participate rather than to just attend so I was happy to see that the organizers had set up the ‘Angel’-system also used during the CCC congresses for people to sign-up for helping with various tasks during the event. I singed myself up for some video streaming and recording shifts, for looking after hacker kids for a while and also ended up helping to prepare lunch for the team. A nice mix. But besides being part of the conference and talking to people I also went there primarily for the talks. Here are my personal recommendations (most talks are in German, however) from the great choice now online at media.ccc.de:

Continue reading Recomended Froscon 2017 Talks

Slowly but steadily the SSDs in the notebooks in the family keep filling up so at some point in the not too distant future I either migrate from 1 TB to 2 TB SSDs or have to think about strategies to put some of the files to offline/home storage. While I would obviously prefer the first option the reality is that SSD prices haven’t dropped much over the past 3 years. Where’s Moore’s law? Continue reading 1 TB SSDs the same price as 3 Years Ago

Back in 2014 I was musing about that the time has come for network operators to introduce a feature to hand-over an ongoing 3G connection to LTE. For me and those who frequently tether their PC while on the move, this is an important feature when the network makes a handover of an ongoing connection from LTE to 3G. Without the feature a device is stuck in 3G unless the radio bearer is released and the mobile can reselect back to LTE autonomously. Another way back to LTE is when the connection is transferred by the network to 2G at some point as here, the mobile can take measurements on LTE bands autonomously even while a data transfer is ongoing and reselect back to LTE. Unfortunately not much has happened in in that regard since then and I continue to be stuck on 3G for a long time when using my notebook. But when I was recently traveling I observed a number of 3G to LTE ‘handovers’ while a data transfer was ongoing for the first time. And it worked a bit differently from what I expected. Continue reading 3G to LTE Handover – Another Approach

When I travel on business I usually have two notebooks with me as I like to keep things apart from each other. It’s a bit of a pain, especially in conferences when desk space is limited but the setup has served me well over the years. When I was recently on business travel I decided I take the chance and use a virtualized instance of one of the two computers and run it on the other.

Continue reading ‘Inception-Like’ Working Across Continents with LTE and 3G

This time I was a bit less surprised when I received a CMAS warning message. However instead of a test message like in the Netherlands it was a real warning message from the US National Weather Service. Perhaps this is a normal occurrence for most Americans but in Europe only the Netherlands is using a cellular network public warning system so it’s still worth to blog about it for me.

I also noticed that stock Android has adopted a lot of configuration options to enable users to select which kind of warning messages they want to receive. The second screenshot on the left shows the options as implemented in Android 7. In LTE, CMAS or WEA (Wireless Emergency Alerts) as the system is now referred to is implemented by broadcasting System Information (SIB)-12 messages. For further technical details have a look at my post on the topic from last year.

Continue reading US National Weather Service Alerts Me With WEA

I’m a frequent international traveler, so easy and affordable voice and data connectivity not only at home but also when traveling are obviously very important to me. Recently, things have once again significantly improved as the the US and Canada are now also included in my German mobile subscription.

Continue reading Intercontinental Flatrate

From the number of book reviews it must seem that I do quite a bit of reading these days. However, it’s not more than usual, I just have some catch-up to do. Back in 2015 I had a post on “Diary of an 80s computer geek“, a book not about events that shaped computing history but rather a personal story of how computers in the 1980s had on the author. “A Terrible Nerd” by Kevin Savetz is another book in that rare genre, written from the perspective of a teenager and young adult in the 1980s in Southern California. Again there are many stories he tells I can immediately relate to as I had similar experiences back in those days. Like me, Kevin seems to have found interest in computer archeology and he’s quite active in the Atari domain preserving documents and hardware. A great book if you want to step back for a little while from stories about how particular computers, persons and inventions have shaped the industry and just want to dive into personal computing experiences from the 80s.