Hacks and Gadgets by HJL

This evening I started having the same problem with my Thinkpad T42p as the one I had a few weeks ago with one of the LCD monitors, which is that has started blacking out the backlight at random, typically a few seconds or minutes after starting up the system. In my case, it was easy to determine that the graphics subsystem was working fine, as I normally have an external monitor connected already, which didn’t have any problems at all. That leaves the LCD panel, backlight, and inverter as likely suspects.

I found some handy resources for diagnosing and repairing notebook display problems:

Here is part of an e-book on diagnosing notebook problems, this section is Notebook LCD Display Monitor Problem

Here is an illustrated step-by-step guide to disassembling an IBM T40/T41/T42/T43 display bezel and replacing the LCD backlight inverter.

For now, the temporary workaround is to simply reduce the screen brightness to 6 bars instead of 7 bars. So far this seems to reduce the stress on the inverter and/or the LCD backlight enough that it doesn’t shut down any more.

One of the LCD displays on my desk recently started flickering on occasion, and this afternoon started going completely blank. In a quick round of testing, I discovered that the graphic card works fine with other displays, and that the problematic display would actually work for a few seconds immediately after power on before the screen turned black.

A quick Google search shows that this is a fairly common problem among LCD panel displays from many manufacturers, and typically involves a problem with the power supply for the LCD backlight. One fix apparently involves replacement of several electrolytic capacitors in the power supply.

In the meantime, reducing the screen contrast and brightness has temporarily fixed the problem. It seems to be somewhat heat-related.

I tripped over a bit of DOS arcana this afternoon while setting up a new digital picture frame. I was copying a folder containing a few hundred JPEG files into a 1GB flash card using Windows XP, and eventually got an error dialog saying something like “can’t create file”. At first I thought perhaps it had run out of room, as I didn’t bother resizing the original image files before copying, but there were still a few hundred megabytes left after copying over 250 images to the flash card.

This reminded me of a problem I encountered in the stone ages of personal computing, which is a limitation of the original DOS file system. Basically, you can’t put too many files in the root directory of a DOS file system, as there is a fixed and relatively limited storage space assigned to it when the file system is created. If you want to put hundreds of files on a DOS16 file system, you need to use subdirectories. The DOS16 file system is widely used by many flash-based devices including digital cameras, music players, and USB sticks, even though it’s rarely used by desktop systems today. The Windows XP and Vista error messages for the full DOS root directory problem are cryptic at best, so I suspect others may come across this problem while setting up their digital picture frames and similar devices after the holidays.

If you are having a problem copying files onto your flash card or USB storage device, and it’s not actually full already, try creating a subdirectory or two to hold your files instead of copying them to the root directory.

My wife has an original iPod Mini which has been slowly losing its ability to hold a charge. The correct solution to the situation is inevitably going to be replacing it with one of the updated iPod Nanos, but this involves selecting a color first, which is out of my hands.

In the meantime, I saw a battery replacement kit at Fry’s this afternoon and thought I would try rehabilitating the Mini, since it’s in good condition, other than having a battery life of about 30 minutes. I also remembered reading a few articles on the subject a while back.

I got a kit made by Premium Power, which supplies a lithium-ion battery, plus a small screwdriver kit and instructions. It was around $40 at Fry’s, but is available online for around $18. I believe Apple also provides a mail-in service for replacing the batteries, but I was taking the instant gratification approach here.

The front of the packaging says it includes “easy installation instructions”, while the back provides a caution - “installing this battery requires a moderate level of technical ability and proficiency in the use of hand tools as well as a general understanding of electronic components.” There’s also a warning that disassembling your iPod will void the warrantee, but in our case it expired a long time ago.

Once you get the iPod case open, it’s not bad. The primary challenge is getting the two end covers off. They are glued onto the ends, so prying them off pretty much requires inflicting minor chipping somewhere on the plastic. You can see the adhesive in the photo above.

The replacement battery was about a half millimeter larger than the original one, and fit more tightly in the limited space. It looked like it might not make it back into the metal housing, but actually did fit with some careful jiggling.

I wouldn’t recommend the DIY approach to battery replacement to anyone uncomfortable with following directions or handling small parts. The “easy installation instructions” are easy to read, but following them is probably beyond the average person’s comfort level.

This unit is likely to be retired to backup duty shortly, but if you’re like me, hate discarding perfectly good electronics, and aren’t scared off by the instructions, replacing the battery can give your iPod Mini an extended life.

I recently decided to give another try to using a Bluetooth headset, and this time around I’m quite happy. I last tried using a Bluetooth headset a few years ago and was unimpressed, both by the high price and by the poor usability. My usual handsfree solution since then has been to use the speakerphone mode on my phone. This works well in the car if you’re by yourself, but can be problematic if others are riding with you.

I wanted a headset that would work with my Nokia 6820 as well as voice applications on my notebook computer, and found the Plantronics Voyager 510, which is able to pair with two devices supporting either the Bluetooth handsfree or headset device profile. The sound quality is good, comparable to a wired headset, it’s comfortable enough to leave on for hours at a time, and the battery life lasts more than a day. The wireless connection works from my desk to anywhere in my office, I’ve tried it to 15-20 feet or so, and also stays connected if I leave the phone in the car and walk around to fill the gas.

The headset can be set up for use on either the right or left, and comes with three eartips of different sizes along with a pair of microphone windscreens.

I’ve been using the headset for the past few days, including several hours of driving between Palo Alto and Los Angeles, and so far am impressed with the improvement over the early Bluetooth headsets, which were expensive, bulkier, sounded worse, and didn’t work well with the cell phones. This may push me back in the direction of getting a smarter phone / PDA device again.