More on computer hardware choices
To the editor:Thank you for the recent article on computer hardware ("Hardware decisions," Issue No. 96, March/April 1999) by Daniel Piltch. In my experience, there are several other issues that also warrant mention.
When considering mounting a laptop on your vessel, especially computers of more than 200 MHz or those that have add-in memory, be sure to allow open air circulation on the portion of the bottom surface that gets hot. Be especially careful not to obstruct any vent holes. In conditions of high ambient temperature, from geography, seasons, or UV absorption through the windows on black casework, give the computer good air flow to carry away the heat. In particular, one photo in the article looks like the computer is tied down on a foam pad. This is great for older (cooler, slower) computers, but a different arrangement is needed for the faster ones.
Mariners relying on the battery power of the laptop as emergency supply might consider that additional memory, extra drives, maximum display brightness, and continuous powering of the serial port will reduce the battery power reserve to small fractions of the advertised value.
One option for the not full-time use of the laptop for navigation is the docking station. It is often easier to permanently mount a docking station than a computer. A hard drive in the docking station can hold all of the charts, logs, and navigation software, freeing up the much more expensive space on your take-away laptop. Backup and recovery strategies are both improved with this configuration. As the docking station has a key lock and mechanical mounting specifically built for the laptop, mounting and security issues are also easier.
Many on-board users may find using a mouse inconvenient. My experience is that touch pads don't respond well to cold, or wet, or callused fingers. My favorite input device is the remote trackball made by Logitech, which uses an infrared link. You can stay in touch with the computer from any location, without wires. Along the same theme, active-matrix LCDs are brighter and can be seen from a wider field of view than passive-matrix LCD screens, albeit at a premium price.
The article might have added the advice that amateur installations, especially in power supply and cable connections, may seriously jeopardize reliability in an already complex instrument. In my opinion it's a good idea to have a professional marine electronics technician with a good reputation do the install or at least do a commissioning inspection.