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Fldigi (Fast Light Digital Modem Application) is a cross-platform modem program that supports most of the digital modes used on the amateur radio bands.

Fldigi is a digital modem program for Linux, Free-BSD, OS X, Windows XP, W2K, and Vista (probably Win7).

Bill – WA5PB

computer sound cards, so many uses!

The PC sound card may just be one of the most useful electronic devices that nearly everyone owns.   Not only can you listen to music with it, but you can do nearly any Ham Radio digital mode.   However, did you know you can also use your PC+sound card combination as a spectrum analyzer or even as an Oscilloscope?   Here are links to software that will allow you do this.  Both are easy to install and free.

Spectrogram 5.17 – for Windows.   I did all the xtal alignment work on my Elecraft K2 radio with this program.

Baudline – for Linux, Mac OS X, and Solaris SPARC systems.   This one has LOTS of features.  Simple to install!  Download, unzip, and run the “baudline” program from the unziped folder.

Bill – WA5PB

Linux games! (didn’t you know?)

Yes, Virginia, there are Linux games and good ones too!
You might not be much into gaming, but hey, you might get bored one evening. Here are some good Linux games of various sorts. All for FREE.

Cool list of 5 great Linux games in 2010 (various). BTW, Dedoimedo is a great blog!

For those who LOVE WWII and the battles! Computer version of the classic boardgame Axis & Allies. For all platforms, extract zip into a folder and run the OS appropriate OS triplea file.

Battle for Wesnoth. Turn based fantasy strategy game. Play the computer or others online.
Install version wesnoth-1.8 from the Ubuntu repostiory.

Ubuntu comes with some solitare type games already loaded, but if you want many more then install PySol from the repository.
Includes many, many types of games including Majong and others, really worth installing.

The opensource version of one of the best games of all time, Civilization, as FreeCiv.
Install freeciv from the Ubuntu repository.

GIMP – a deskew plugin

GIMP (the GNU Image Manipulation Program) is a great product.  It provides many advanced image editing options and is available on both the Linux and Windows platforms.  Of course, it is FREE.  One capability that is noticed to be missing from its sizable suite of tools is a “deskew” function.   As the name suggests,  a deskew function straightens up a somewhat crooked picture.  This is often needed to straighten up a scanned image that did not pass through the scanner in a perfectly straight manner.   After quite a lot of searching on the web, I found that there is a plugin (an add-on) that provides this function for GIMP.   For the typical user, getting ones hands on the deskew plugin is not as easy nor is installing it intuitive, so I will provide links to both the Linux and Windows versions of the deskew plugin and instructions how to install each.

First download the plugin for your OS:

GIMP-deskew-plugin for Windows
GIMP-deskew-plugin for Linux

To install in the plugin into GIMP for Windows, unzip the plugin from the file you downloaded and place the deskew.exe file in the c:\program files\gimp\lib\2.0\lib\plug-ins\ folder.

To install the pluging into GIMP for Linux, simply place the pluging you downloaded, the deskew file, into the /usr/lib/gimp/2.0/plug-ins/ folder.

Now, either open GIMP or close and restart the program if you already had it open. You will now find a new entry in the Filters menu called Misc. The plugin is selected via the menu path Filters>Misc>Deskew.

NOTE: I did not write the GIMP deskew plugin, and thus cannot provide any support for it. I just want to make it easily available to other GIMP users since it took me some time to find both versions.

bye bye Ubuntu 10.10

It is with a sad heart that I have backed up my files off of my laptop running Ubuntu 10.10, aka Maverick Meerkat, and reloaded from scratch with the previous version, 10.04, or 10.04.1 specifically. I have typically liked to keep up with the latest, greatest version of Ubuntu with the 6 month releases. In that vain, I upgraded my 10.04 system to 10.10 when it was released. I was not cetain there were any new features that I really needed, and 10.04 was working flawlessly for me, but I just went ahead and dove in headfirst and upgraded. That was a mistake. I immediately noticed some glitches in the screen savers and then discovered that there had been radical changes in the Bluetooth management. I often use Bluetooth to tether my 3G phone and surf the web. Under 10.04, the default Bluetooth manager would not handle this type of arrangement in a convenient way. So, all one had to do is install the Gnome default Bluetooth manager, blueman. It paired with the phone effortlessly this way and then the network manager was used to create a DUN dialup connection for the particular cellular provider. It worked perfectly. Ubuntu 10.10 broke blueman. The default network manager was redesigned to basically combine the functionality of blueman and also streamline the creation of the DUN connection for Mobile Broadband. Looked nice, but unfortunately did not work well at all. It absolutely refused to easily pair to the phone without repeated pairing attempts and then when I finally got it to pair and created the Mobile Broadband connection and get on the web, it would not seem to hold its settings requiring a complete recreation of the connection settings every time I wanted to use it. I needed this to work for me out in the field today and it failed me, causing me much lost time and effort. This upgrade was a REGRESSION! Yes, the dreaded “R” word. I should have know that this release was not going to be a good thing when both I and a friend experienced strange behavior post upgrade to 10.10 on very different systems. Then within days, Ubuntu was pushing down over 400 megabytes of sudden critical updates. Seemed strange at the time, but now I know why – 10.10 was broken, still is in some ways as I have described. I learned a serious lesson this time. Never upgrade and good, stable LTS edition of Ubuntu for the latest greatest 6 month release without thoroughly testing the new release on a separate system. So, I post this blog from a nice freshly installed 10.04.1 build of Ubuntu. Goodbye Maverick Meerkat, it was not nice getting to know you. May you be eaten by a Jackal.

It gets even worse for Microsoft

It gets even worse for Microsoft. As I mentioned in my previous blog entry, Linux is beginning to catch up with Microsoft Windows in the workplace. However it is not only Linux doing this. Windows file servers are now often replaced with NetApp filer appliances. Well, NetApp is not based on Windows and it makes one or more Windows servers go away. While the NetApp OS, Data ONTAP, it is not based on Linux, it is based on other members of the Unix family.

Linux is on the Rise for Business

This is good news for the Linux world.   As Linux becomes more adopted by business, its usage in other areas is also more likely. Linux is on the Rise for Business

A great Linux/Unix shell resource

I am a BIG fan of the old adage that says “The best things in life are free.” Of course, one of the very best FREE things is the GNU/Linux operating system. However, to take full advantage of Linux, one should learn the Linux command line . Sure, there are enough books to buy out there on the subject of Linux to fill a library and spend a not so small fortune in the process. But why spend that money and fill bookshelves with books you will likely only skim through or outright never read when one of the very, very best books on the subject is 100% free? I am referring to the book by William E. Shotts, Jr. – The Linux Command Line. This is by far the best book on the subject of the Linux command line and scripting that I have ever read. The truth is, it is one of the best books on this subject for Linux or Unix out there. While specifically targeted at the Linux operating system, much of it is applicable across the whole family of what is called Unix-like operating systems including Linux(in its many various distributions), the BSD Unix family(FreeBSD, NetBSD, OpenBSD, etc.), System V Unix systems including Solaris/OpenSolaris, HP-UX, and even Mac OS X. In truth, all of these operating systems share far more in common in their use of the command line and utilities than they differ, so The Linux Command Line is a great resource for them all. I highly recommend this book!

Useful Linux tips

This page has some very useful Linux tips.  Mainly for beginners, but some intermediate.   Good stuff!   Thanks to the author for sharing with the community.
Highly useful Linux commands & configurations


Why script writing in the Unix shell csh is considered harmful.   A classic, but useful, Usenet rant.

HOWTO – Ububtu, a customizable Compose Key System

In my previous blog entry, I introduced both Unicode character entry and Compose Key entry of special characters.  One thing that becomes apparent is that there might be some characters or symbols missing from the default GTK+ code in Gnome.   Unfortunately, this is in compiled code and cannot be changed.  One option is to use Compose Key sequences for most special character entries and Unicode character entry for the occasional odd symbol.  However, if that “odd symbol” is one you intend to use often, you might wish you had a Compose Key sequence for it.   This can be accomplished, at a small price.

Situation, say you are an electronics enthusiast and have a need to type the Ohms symbol, Ω, quite often.  This symbol is not in the default GTK+ Compose Key sequences, and there is no way to add them easily into that source.   An option is to use the <Shft><Ctrl><u>03A9 Unicode method entry to get the Ohms symbol.  Sure, this works fine, but could be tedious if done on a regular basis.  What we need is a way to get this into a nice, intuitive, Compose Key sequence.  The solution is to take advantage of the fact that there is an alternate source for the Compose Key definition table and that this can be modified to add in missing symbols that you may need to use often.   This is the .XCompose file, which I will show here how to create and edit.

The method we will use is to override the default Gnome method with the orignal Xwindow method, which is also available on your system, but must be configured and activated.  It is called the Xwindow Input Method (XIM).  The system must be told to use this method instead by setting the GTK_IM_MODULE environment variable.   This is done with the following command from the shell prompt:

export GTK_IM_MODULE="xim"

For this environment variable setting to be automatically set every time you log into the system, add this line to the .gnomerc or .Xsession file in your home directory.  If these files do not exist, then create one (.gnomerc) by entering the following text in any text editor and saving the file as .gnomerc (do not neglect to include the leading dot!):

export GTK_IM_MODULE=”xim”

Next, you want your own copy of the XIM Compose Key file to have and modify to your own liking.   We do this by copying a system copy of the file to our home directory and giving it the name .XCompose (this file name is CASE SENSITIVE!):

cp /usr/share/X11/locale/en_US.UTF-8/Compose ~/.XCompose

Finally, you will want to edit your .XCompose file to add in the symbols and keybindings  you are interested in.   For instance, here are the lines I added to bind the Unicode 03A9 for the Ohms symbol to <Multi_key> (AltGR in my case, whatever you have set as your Compose Key in your case) <o><m> (get it?) and <m><o>, also some other symbols I find handy.

<Multi_key> <o> <m>                   : “Ω”   U03A9 # OHM SYMBOL
<Multi_key> <p> <i>                    : “π”   U03C0 # PI SYMBOL
<Multi_key> <d> <t>                    : “Δ”   U0394 # DELTA SYMBOL

Is there a downside to overriding the default Gnome GTK+ Compose Key tables?  Yes, there is.  You loose the <Shft><Ctrl><u> keybinding to be able to do Unicode entry anywhere in the Gnome interface.  However, if your aim is to exclusively use Compose Key sequences and to update your data table to include any missing ones you might need, then it is not a bad trade off.

Finally, a tip on editing the .XCompose file.  Just how do you enter a represenation of the missing symbol into the file if you have already activated XIM which disables the <Shft><Ctrl><u> Unicode entry method?  Edit the file in an editor such as Vi that has its own Unicode entry method or use the Gnome “Character Map” utility to get a copy of the symbol into an editor that does not have a method of its own.   In Vi (or Vim), go into text insert mode and type <Ctrl><v><u>+unicode to enter Unicode symbols.

Once you have set the environment variable and created your file, log out and then back in to activate everything and you are all set to have a Compose Key system that you can customize to suit your own needs.

Much of this information was extracted from the following source and should be referred to for further information on the subject:

HOWTO – Ubuntu special characters

In Ubuntu, if you want to type any Unicode character, do so my holding down Shift+Ctrl+U then the unicode for the needed character.  Shift+Ctrl+U gives you an underlined u and you type the code and hit <enter>.  Works in every application I have tried.


Shift+Ctrl+U 00f4 results in ô
Shift+Ctrl+U 00e1 results in á

Of course, you have to know the Unicodes.  This chart will help

Also, you can use the COMPOSE KEY!

Addition information on configuring a compose key sequence and its use can be found here:

I defined my compose key to be the Right-Alt key on Ubuntu 10.04 like this:

System>Preferences>Keyboard>Layouts>Options>Compose key position>Right Alt

Good list of compose key combinations to get all the weird, odd and desperately needed characters you want:

Wikipedia entry on Compose key:

Another blogger’s nice short write up on using compose keys:

Finally, for Windows users who would like to have Unix/Linux style compose key functionality this program works well and is free:  AllChars

Ubuntu, when things go badly – Synaptic HOWTO

This is good information for anyone who is going to be managing an Ubuntu system.

also good documentation on using the shell interface for Apt

I had a 9.10 to 10.04 upgrade break due to an internet failure during the process.   The following is from the SynapticHowto.  The upgrade was so broken that it was leaving me at a shell prompt to login, the Gnome desktop was not loading automatically and the Update Manager would not finish the upgrade.  I did the following and it saved my upgrade and got everything working properly.

Broken Upgrade or Installation

  • What to do if an installation process fails and you find it is no longer possible to install or remove packages:
  • Open a Terminal and type the following commands, pressing the Return or Enter key after each (you may have to type in your password):
     sudo dpkg --configure -a
     sudo apt-get install -f

a neat trick via Ghostscript

I have found a neat trick.  Not original, found it here:

PostScript and PDF

  • To concatenate PostScript or PDF files into a single PDF file:

    gs -q -dNOPAUSE -dBATCH -sDEVICE=pdfwrite \
    -sOutputFile=<outfile> <infile> <infile> …

  • To concatenate PostScript or PDF files into a single PostScript file:

    gs -q -dNOPAUSE -dBATCH -sDEVICE=pswrite \
    -sOutputFile=<outfile> <infile> <infile> …

  • This trick used in combination with the fact that in Ubuntu you can print not only to a printer, but also to either a postscript or PDF file directly, means that if a book is presented in html on the web, say with each chapter being an individual HTML page, you can easily print each of these to a file and then use the trick to concatenate the ps or pdf files together to reassemble the entire book.  For instance, I am doing that with this book that is online:

    I do not know how many other books that I have run across on the web that were HTML like this and I wanted to reassemble them for a good print out.  This is a way to do it.

    By the way, “gs” is the command line program for Ghostscript, which should be already installed on your Ubuntu system by default.  If you install Ghostscript on a Window system, the same trick should work there too so long as you print the HTML to a PDF printer driver.  Ghostscript can be downloaded from here:

    Oh, yes, this is also cool…:

    Why Desktop Linux (still) Sucks…


    This is not a slam against Linux.  It is all about making our favourite OS more viable and available to more people.

    Ubuntu 10.04 LTS is released

    The new Unbuntu, 10.04 LTS, has been released. It is great!
    Go get Ubuntu 10.04.
    A good review from another blogger: Ubuntu 10.04 – Perfect

    The Magic SysRq key

    The Magic SysRq key!   If you use a GNU/Linux OS, discover what the SysRq key on your keyboard can do for you.