Morse Decoder Test - iPhone / iPad

There are three morse decoders in the App Store. Same test case for all of them: "CQ CQ CQ DE DG6FL DG6FL K" from memory of my palm paddle with 20wpm.

Video of the test

1. MorseDecoder (HotPaw Productions)
   Seems to work
2. MorseDec (Luca Facchinetti)
   Room for improvement
3. Morsepad (Black Cat Systems)
   Does not work at all

Converting LaTeX to ePub

In contrast to claims in the web (i.e. M. Kofler: Sackgasse LaTeX?) it is possible to create ebooks from LaTeX sources easily even with sophisticated formulas and custom stylesheets. Using calibre and tex4ht I was able to provide an ePub of my PhD thesis: Atomistische Simulation von Nanoindentation. The resulting output looks quite impressive (minor defects when it comes to image boundaries or subscripts in text blocks). For comparison the original PDF.

Cross Glide

Raspi As WSPR Transmitter

Recently the Raspberry Pi (Raspi) has gained much interest in the Ham Radio community. One interesting things is: the I/O pins provide access to a clock signal (GPCLK0) and it is possible to modulate this clock signal via software. This has motivated Guido Ten Dolle (PE1NZZ) to implement a WSPR transmitter and to publish the sources under GPL. Within the last days I have made some minor modifications to the WsprryPi sources, built a 30m QRP filter using the ugly method and connected everything to my doublet antenna.

Raspi as WSPR Transmitter

Immediately my 10mW have been received in 743km distance by G6HUI (WSPR Spots):

Timestamp	Call	MHz	SNR	Drift	Grid	Pwr	Reporter	RGrid	km	az
2013-04-13 15:30	DG6FL	10.140199	-16	-1	JO40cb	0.01	G6HUI	IO81wl	743	286

7869km with 10mW

Timestamp	Call	MHz	SNR	Drift	Grid	Pwr	Reporter	RGrid	km	az
2013-04-22 05:02	DG6FL	10.140238	-21	1	JO40cb	0.01	W4AC	EL86	7869	289

Information on how to do this yourself can be found in the WsprryPi repository.

Mount OSX SMB Share From Linux

A small reminder for all the options:
mount.cifs //1.2.3.4/public /mnt/public -o user=myusername,password=mypassword,nounix,sec=ntlmssp,noperm,rw

Time Machine & Local Snapshots

Time machine can keep local snapshots. While this feature is useful if you travel and don't have access to your Time Capsule, the local snapshots can consume a lot of the local disk space in /.MobileBackups. There is a complex Removal Algorithm for old local snapshots based on the remaining free disk space.

To find out how much space your local snapshots consume (Local Snapshots):

• Apple-Logo → About This Mac → Further Information → Storage: Backup == Local Snapshot Space 
• Alternatively from commandline:
  test -d /.MobileBackups && du -hcs /.MobileBackups

It is useful to control the behavior of the local snapshots yourself (Controlling Local Snapshots) using tmutil disablelocal and tmutil enablelocal.

Downloading the Google Latitude History of a Year

It is possible to download the google latitude history of a complete year in one step:
https://maps.google.com/locationhistory/b/0/kml?startDay=01/01/2012&endDay=12/31/2012

Start VNC Server on OSX from Commandline

The builtin VNC server can be started using commandline (i.e. with ssh). As root do:

cd /Library/Preferences
echo enabled > com.apple.ScreenSharing.launchd
touch /etc/ScreenSharing.launchd