Posts
Using an Epson Perfection V30 scanner in Linux
When I was shopping for an inexpensive flatbed scanner, it was not always easy to figure out which ones would work in Linux. Many manufacturers use proprietary protocols in their products and generally ignore Linux. I bought an Epson V30 because it was cheap and because there are drivers available for download here . The drivers work on Linux Mint 6 (Ubuntu 8.10) or later, and on several other Linux variants. Unfortunately source code is not provided, so if you don’t have one of the popular distributions, you may be out of luck.
October 4, 2009
Re-gluing hammer felts on a grand piano
Last year my 1994 Mason & Hamlin BB (a 7-foot grand) developed a very unusual and alarming problem: several of the hammer felts in the mid-bass section came unglued. along the front side of the hammer. Thankfully the felts remained glued along the back side; otherwise they would have fallen off completely. My piano technician called the M&H factory to ask for advice, but since the company changed ownership after my piano was built, and the piano was out of warranty, he wasn’t able to get any satisfaction. So he took the action away for a week and re-glued the felts with hide glue. This was a quick and dirty patch job. The ideal solution is to replace all the hammers, but that’s a very expensive, time-consuming operation.
September 3, 2009
Printing USPS Click-N-Ship labels in Firefox on Linux
I use the USPS web site to print shipping labels, and each time I upgrade to a new version of Firefox or Linux, I always run into the same problem: printing labels doesn’t work. As soon as I click the Pay and Print button, Firefox goes into some kind of infinite loop reading data from the USPS web site, and the PDF file containing the label is never seen. The fix is to change how PDFs are handled by Firefox so that Adobe Reader is started as a separate process, rather than as an embedded window inside Firefox. Here’s how to do that in version 3.0 of Firefox:
June 11, 2009
Paper: a display technology for the future?
What with all the talk about new portable devices such as netbooks and the Amazon Kindle, an older but still promising portable display technology called “paper” has been largely ignored. But that’s a shame, because paper has many advantages that electronic devices still don’t come close to equaling. At first glance, paper might seem like an awfully crude technology; it’s made from flattened-out wood pulp, after all. But this allows it to take on shapes and sizes only dreamed of by conventional displays. Take newspapers, for example. Their display size and resolution are enormous by today’s standards; equivalent LCDs would cost thousands of dollars. Also, newspapers are light in weight, and can be folded up for portability.
June 11, 2009
Fixing microphone input on ThinkPad R61 in Ubuntu / Linux Mint
Yesterday I tried using the internal microphone on the ThinkPad R61 for the first time, in an attempt to make a Skype call. Skype kept saying there was an error in the sound configuration. After the usual Google searching and flailing about, I made the following changes to my system to fix the problem. It’s not clear whether all of these changes are necessary, but using them all certainly doesn’t hurt.
May 2, 2009
Three Bad Designs
Most modern computers, and especially laptops, are afflicted with three especially poor design choices. We seem to be stuck with these choices, because the market, in its infinite wisdom, has decided that they are somehow an improvement over the old ways, or at least different. I’ll start with the oldest problem first. Caps Lock in the wrong location Up until around the mid-80s all terminals and computer keyboards had a Control key placed where God intended it, next to the A key on the home row. This was extremely convenient when using programs like editors (especially Emacs and it imitators). Even Windows has plenty of keyboard shortcuts that use the Control key. So having that key within easy reach was a big plus.
March 2, 2009
Upgrading from Rails 2.1 to 2.2
I have a small project that I developed at work using Rails 2.1. After installing the latest version of Rails, 2.2.2, I had to do the following to get my project working again: Edit config/environment.rb and change the value of RAILS_GEM_VERSION to ‘2.2.2’. Edit config/environments/development.rb and comment out the config.action_view.cache_template_extensions line. Run rake rails:upgrade. This added a new file, script/dbconsole, and modified the following files: config/boot.rb public/javascripts/controls.js public/javascripts/dragdrop.js public/javascripts/effects.js public/javascripts/prototype.js
February 25, 2009
Power-off fix for Linux Mint 6 / Ubuntu 8.10
The older computer on which I installed Linux Mint recently wouldn’t power off properly after a shutdown. This used to work on Mandrake 10.2. Apparently the problem is due to the newer Linux kernels requiring ACPI by default for power management, and this machine’s BIOS doesn’t seem to provide a compatible ACPI implementation. After the usual slogging through Google search results and numerous experiments, the fix was extremely simple: add the following line to /etc/modules:
February 14, 2009
Fixing screen resolution in Linux Mint 6 / Ubuntu 8.10
I installed Linux Mint on my parents’ computer today, replacing Mandrake 10.2. (Yes, grandparents can use Linux.) This older computer has a motherboard with a built-in VGA adapter by Trident, connected to an ancient CRT display with a maximum resolution of 1024x768. But for some reason, Linux Mint set the resolution to 800x600, and the Screen Resolution tool in the Control Center would not allow it to be set higher.
February 10, 2009
Batch resizing images in Linux Mint / Ubuntu
I recently switched my two main laptops to Linux Mint . I’ve been running KDE-based Linux distributions for years, and this is my first experiment with Gnome. Right away, I discovered that there are apparently no Gnome applications that can resize multiple images as easily as the premier KDE photo application, Digikam. GThumb, an otherwise decent photo viewer, has a memory leak bug in its “scale images” feature that quickly brings the system to its knees; this bug was supposedly fixed long ago but has resurfaced in Ubuntu 8.10. The batch plugin for Gimp looks like it ought to work, but almost always fails with various errors.
January 5, 2009