My MacBook suddenly decided it didn’t have an Airport card, reporting the error “No Airport hardware found”.

I fixed it by doing an SMC reset:

1. If the computer is on, turn it off.
2. Disconnect the AC Adapter and remove the computer’s battery.
3. Press and hold down the power button for 5 seconds and then release the button.
4. Reconnect the battery and AC Adapter.
5. Press the Power button to restart the computer.

Hat tip: Bruce Snyder

UPDATE: This fix also worked for repairing a “Bluetooth: not available” error. It may have helped repair a problem I’ve been having lately with the WiFi dropping in and out.

Using Knoppix 5.1.1 DVD installation.

su -
wpa_passphrase SSID TextPassphrase

Result is a hex passphrase.

Create /etc/wpa_supplicant.conf :

ctrl_interface=/var/run/wpa_supplicant
ctrl_interface_group=0
eapol_version=1
ap_scan=2
fast_reauth=1

network={
ssid=”SSID”
proto=WPA
key_mgmt=WPA_PSK
pairwise=TKIP
group=TKIP
psk=HexPassphrase
}

To start wpa:

wpa_supplicant -D wext -c wpa_supplicant.conf -i eth2

To get IP info:

pump -i eth2

When trying to sync an iPod with iTunes, a ‘1418′ error appears, and says that it can’t communicate with the iPod.

Thanks to a comment post in this thread.

• Find the iPod drive in My Computer.
• Right-click it, select Properties.
• Select Apple iPod USB Device.
• Select Policies tab.
• Select Optimize for performance.

Firefox Download Manager (Firefox 2.0, MacOS X) shows up, but is completely blank, and the folder name is missing.

To fix this, you need to create a completely new profile.

cd /Applications/Firefox.app/Contents/MacOS

./firefox -ProfileManager

Then cd to the new profile directory (under ~/Library/Application Support/Firefox/Profiles).

Copy bookmark* and cookie* from the old profile.

The ukrepeater.net site helpfully provides a .csv file listing all the UK repeaters, with details of the technical information required to use them (such as frequency, and CTCSS tone).

VX-Commander, a great tool from Jim Mitchell (KC8UNJ), allows you to program your radio using a PC. It will accept a .csv file as input.

However, the repeaters.csv file isn’t in the right format for VX-Commander. So I wrote a couple of Python scripts to munge the data into the required format for VX-2 Commander and VX-7 Commander (as I have a VX-2E and a VX-7R).

The scripts are easy to edit and run. Just dump the repeaters.csv file into the appropriate directory (which you can adjust in the script). Run the script, and the resulting vx2.csv or vx7.csv will be produced. This file can be imported into VX-Commander.

Obviously, vx2.py produces output for the VX-2, and vx7.py for the VX-7.

UPDATE: The csv format has changed, so these scripts no longer work. See the updated version for the VX-3 here.

When generating a pseudo-random binary sequence, it’s hard to create a series of bits that is evenly distributed for all lengths of sub-sequence; by that I mean that even if you get roughly the same number of 0s and 1s, you might get wildly different counts of 00s, 01s, 10s and 11s. And you might have different counts of 000s, 001s, 010s, 011s and so on for all sub-sequences. Any of these variances can signify a non-random sequence. It has (so I’m told) been proven that it is impossible to generate a genuine pseudo-random sequence that satisfies the requirement of having a reasonably similar distribution of all sub-sequences. But I had this idea a few years back. Why not keep a count of all the sub-sequences, and select the next bit based on the longest sub-sequence that is deficient? With a powerful scripting language like Python, it’s pretty simple to knock up an experiment.

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Hurricane Rita and Continental Airline

The last part of my trip involved a flight from Las Vegas to Houston on Thursday 22 Sep, and a flight from Houston to London on the evening of Saturday 24 Sep. By Tuesday, it was becoming clear that Hurricane Rita stood a strong chance of hitting Houston on Saturday morning, so it didn’t look like a good place to be going to.

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I thought it would be neat to take a photo of two very different ‘computers’ next to each other.

At the bottom is my Fujitsu Loox 720, running SpaceTime - a fantastic graphing calculator application for the Pocket PC.

Above it is my grandfather’s slide rule, which he used while working on the steam catapult. For his part in the success of the project, he was awarded the B.E.M. (British Empire Medal).