The WSANDERS.ORG Blog is Still Around 
Even though WSANDERS.ORG is expired, the ham radio and Mother of all Junk Boxes posts are still there:

http://wsanders.net/blog/

Some permalinks to most-viewed entries:

Kenwood Upside Down DIN-13 ACC2 Plug
RFI Fix for Oregon Scientific Weather Station
Advice For New Baker To Vegas Stage Volunteers
The Galveston Hooter is Destroyed
The Hat Museums of Europe

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Dept. of "Why Didn't I Think of That": Getting Average Brightness of an Image 
Using convert, resize the image to 1x1 pixel, and get the image stats (in HSV):
convert original.jpeg -colorspace hsb -resize 1x1 txt:-

Credit goes to this guy: http://stackoverflow.com/questions/7935 ... brightness

However, the Python PIL package will do this for you, the results are only a teensy bit different and you can get extrema and RMS for each channel:

>>> from PIL import Image
>>> from PIL import ImageStat
>>> im = Image.open('/tmp/image.jpg')
>>> stat = ImageStat.Stat(im)
>>> print stat.mean
[92.87710129310345, 94.48407707910751, 82.74996830628804]
>>> print stat.rms
[114.97883849032031, 116.21534866014377, 107.79289136583212]
>>> print stat.extrema
[(0, 255), (0, 255), (0, 255)]

Versus

~$ convert /tmp/image.jpg -resize 1x1 txt:-
# ImageMagick pixel enumeration: 1,1,255,srgb
0,0: (91,92,80) #5B5C50 srgb(91,92,80)


Actually I'd go with Python, because all the cool kids use Python and shells are for old people.

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Raspbian Wifi Adhoc Mode - It's Easy If .... 
I gave up trying to get adhoc wifi to work solely by editing /etc/network/interfaces. This, and variations thereof, never worked:
iface wlan0 inet static
address 192.168.0.1
netmask 255.255.255.0
wireless-channel 11
wireless-essid Pi
wireless-mode ad-hoc

What did work was creating an /etc/rc3.d/adhoc script and calling iwconfig directly. This might save you a lot of time:
#!/bin/sh
ifconfig wlan0 down
iwconfig wlan0 mode ad-hoc
iwconfig wlan0 channel 11
ifconfig wlan0 up
iwconfig wlan0 essid "Pi"
ifconfig wlan0 192.168.0.21 netmask 255.255.255.0

WLAN0 does go down every time the other side of the link gets lost due to a reboot, power cycle, or some other problem. I'm working on a way short of a brute-force restart daemon to fix that.

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OSX Yosemite Fail 
Tried upgrading to OSX Yosemite. I should have suspected it was all part of the old Apple Planned Obsolescence Conspiracy:

- Memory constraints on 4GB mid-2011 Macbook Air. Yosemite caches IO more aggressively, so you see memory "95% full". Theoretically this should actually help in most circumstances (since cached IO will gove way for the memory apps need to run), but everything seemed slower, especially Firefox, my most-used app.

- Fan ran at 100% all the time, any time an app was open, even when CPU was nowhere near 100%. Was it hogging the GPU? No way to tell. I did notice several "mdworker" (Spotlight indexing) processes running, probably reindexing everything for the first time. I killed them, but to little effect.

- Forcing one to hold down the power button for a few seconds to power off instead of sleep always leaves you wondering whether you did a graceful or forced shutdown. Lame.

- Lack of a real sidebar in iTunes is annoying and makes it harder to copy stuff from device to device. Others have bitterly complained about the new iTunes, although it didn't seem so awful to me.

- A few apps won't be compatible - check first.

- The rest is all eye candy. Hey, My laptop is not an iPhone.

So upgrade on older machines at your own risk. I restored with Command-R and Time Machine with zero trouble. I had some good books to read and laundry to do, so it wasn't a complete waste of time.

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Fixing Shellshock / Bashhole on Macs 
Bash updates have been available for Linux for nearly a week, but Apple is dragging their heels, or working on a more permanent bug fix. Despite their not-really-reassuring pronouncement that "only ninjas need to worry about this", you do need to worry about this under certain conditions:

- If you have a web server running on the Mac that uses mod_cgi and any cgi that runs bash or any script that uses the "system" or "exec" call without clearing out its environment. That's been bad programming practice for years. The fix: Disable mod_cgi. For Perl-heads, use "-wT".

- There is a DHCP client proof-of-concept, but my colleague Dr Chase tried it with Mavericks and it didn't work. Older DHCP clients might be vulnerable, but I've seen no proof yet.

Best bet - if you have a compiler installed, whether from Xcode or Ports, just rebuild bash. 4.3 has 26 patches you need to install, but it builds with no problems even on my ancient Darwin G4 running 10.5.8. Rename the existing bash and sh aside in /bin, put the compiled versions in their place, and you're done.

So I'm sleeping OK at night.

There are likely to be more patches to bash in the next few weeks as the problem that makes Shellshock possible is deeply entwined in the bash code. You will probably need to rebuild or patch bash, so save your work.

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Our Friend kcmshell4: Starting KDE4 Settings from the Command Line  
In my last job, I has a legacy Nvidia video card on one of my boxes, with two displays joined side to side. Occasionally this setup caused KDE4 to drop the side by side view and revert to a mirrored copy of one of the two displays. My stuff was still running, but hidden, and the KDE start menu was usually gone as well.

And, of course, I usually had some unsaved work in the hidden window. Fortunately, it's possible to restart the KDE randr config app from a shell, and this usually causes my display to regain its side by side configuration. You do this with:

kcmshell4 randr

Kcmshell4 can start a variety of apps and widgets. You can get a complete list of what's on your system with "kcmshell4 --list".


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