Aeronetworks sro - Airborne Linux

The most annoying thing on my Mac is ( was! ) the Adobe Flash Updater .  This annoying program will pop up and steal the focus and it doesn't actually work.  It never succeeds in updating the Adobe Flash plugins. The only way to do an update is to go to the Adobe web site with a web browser and download their apps again and install them manually. Man will only be free,  once the last computer has been strangled  with the power cable of the last router. — With apologies to Didero. There are many pages on the wild wild web that suggest how to suppress this atrocious thing, but I have not seen a method that actually works.  So I hunted all Adobe updaters down with the top , kill and  find commands and then rooted them out with brute force: $ sudo su - password # find / -name "Adobe*app" ...  # cd /Library/Application\ Support/Adobe/ARMDC/Application/ # mv "Adobe Acrobat Updater.app" "Adobe Acrobat Updater.bad" # cd /Applicatio...

GNU Radio on Linux Software Defined Radio requires a reasonably fast computer and won't work properly on a virtual machine.  The heart of Free SDR is of course GNU Radio, from here https://www.gnuradio.org/ and here https://wiki.gnuradio.org/index.php/Main_Page. I like the GQRX program which I use with the RTL-SDR and Great Scott Gadgets HackRF One and these are all very well supported on Linux and Mac as described here http://gqrx.dk/tag/hackrf.   While I can make this work on my Mac, whenever Apple releases a large OS update, I have to re-install the whole house of cards all over again.  This gets very tiring after a while. So to get this lot working and keep it working, I bought a nice new Intel NUC https://www.intel.com/content/www/us/en/products/boards-kits/nuc.html and installed Ubuntu Linux Server 18.04 LTS on it. This is a long term support (10 year) Linux version which means that it will get security updates, but the essentials will remain mor...

If you want to listen to Jupiter sing , bounce a message off the Moon , or bounce off aircraft , random space junk , or meteor trails , talk to a Satellite , or a little unmanned Aircraft , you need a very high gain antenna.  An easy way to make one, is from an old C-band satellite TV, Big Ugly Dish (BUD). Considering that the amount of space junk is ever growing, Junk Bounce Communications (TM) can only improve.  An advantage of Junk Bounce is that it works at any frequency, from UHF up to K-band, so orbiting space junk could become the new ionosphere, a neat radio wave reflector around the planet! To use an unknown dish, you need to find its focal point and then make a little antenna with a good front to back ratio, to use as a feed. Focal Length The focal point of a parabola is easy to find using some forgotten high school geometry: Measure the diameter (D) and the depth (d) of the dish. The focal length F = D^2 / 16 x d Note that an offset feed dish is o...

The older free Numerical Electromagnetic Code version 2 (NEC2) from Lawrence Livermore Lab assumes an air dielectric.  This makes it hard (but not impossible) for a radio amateur to experiment with Printed Circuit Board Patch antennas and micro strip lines. Air Spaced Patch Antenna Radiation Pattern You could use the free ASAP simulation program , which handles thin dielectrics, you could shell out a few hundred Dollars for a copy of NEC4 , You could buy GEMACS if you live in the USA, or you could add distributed capacitors to a NEC2 model with LD cards (hook up one capacitor in the middle of each element.), but that is far too much money/trouble for most. More information on driving an array antenna can be found here: https://www.aeronetworks.ca/2019/03/driving-quad-patch-array-antenna.htm l Air Dielectric Patch   The obvious lazy solution is to accept the limitation and make an air dielectric patch antenna. An advantage of using air dielectric, is that t...

The eternal question : Which is better - EMACS or Vi? OK, this post is actually about the other eternal question! As I use Linux, Mac, Open and Free BSD (Yes, and that other ball of wax too...), I think I can answer objectively: Both OpenBSD and FreeBSD are reasonably easy to download, install and run on pretty much anything. At least, I have not found a server/desktop/laptop computer that it would not run on.  I even ran OpenBSD on a Sparc Station - remember those? OpenBSD Theo De Raadt has a ' cut the nonsense ' mentality so OpenBSD is simpler, with a smaller repository of programs, about 30,000 packages. However, with a little effort, you can install FreeBSD software on OpenBSD to get the rest. After a few days of use, you will know how. The best OpenBSD book is Absolute OpenBSD: UNIX for the Practical Paranoid. In general, OpenBSD feels a lot like Slackware Linux: Simple and very fast. FreeBSD FreeBSD can also with some effort, run Linux programs ...

Compile The Latest gstreamer 1.15 on Ubuntu Linux 18.04 LTS While working on a way to embed Key Length Value (KLV) metadata in a MPEG-2 TS video stream , I found that ffmpeg can copy and extract KLV, but cannot insert it.  There were some indications that the latest gstreamer has something under development, so I had to figure out how to compile gstreamer from the GIT repository, to get the latest mpegtsmux features. The cryptic official gstreamer compile guide is here: https://gstreamer.freedesktop.org/documentation/frequently-asked-questions/git.html# As usual, the best way to do development work is on a virtual machine, so that you don't mess up your host.  I use Oracle Virtualbox on a Macbook Pro.  I downloaded Ubuntu Linux 18.04 LTS Server, made a 64 bit Virtualbox machine and installed the XFCE desktop, to get a light weight system that runs smoothly in a virtual environment. The problem with the cryptic official guide is that it probably works on...

FFMPEG MPEG-2 TS Encapsulation An observation aircraft could be fitted with three or four cameras and a radar.  In addition to the multiple video streams, there are also Key, Length, Value (KLV) metadata consisting of the time and date, the GPS position of the aircraft, the speed, heading and altitude, the position that the cameras are staring at, the range to the target, as well as the audio intercom used by the pilots and observers.  All this information needs to be combined into a single stream for distribution, so that the relationship between the various information sources is preserved. Example UAV Video from FFMPEG Project When the stream is recorded and played back later, one must still be able to determine which GPS position corresponds to which frame for example.  If one would save the data in separate files, then that becomes very difficult.  In a stream, everything is interleaved in chunks, so one can open the stream at any point and tell imme...