Blog

This personal blog comprises whatever I feel like saying on any given day, which often involves topics like new media, journalism, Web technologies, Scheme/Lisp, Free and open source software, societal issues, cinema film, Boston, and humor. Many things noted here are solely for the benefit of future Web searchers trying to solve particular esoteric problems, and are not of general interest. This blog is largely insulated from my professional life, and vice-versa. I attempt to provide full disclosure of potential conflicts of interest. My site currently gets over 1000 unique visitors a day.

ThinkPad T60 Feedback Noise and Microphone

If your IBM/Lenovo ThinkPad T60 makes a high-pitched squeal when the speaker volume is set near maximum or (oddly enough) when your arm or some other object is placed just so with respect to the T60, then you might have a form of microphone feedback.

The solution (short of fixing the audio hardware and/or drivers) is to mute the mic.

Apparently this is a not-uncommon problem. I thought that the mic might be involved in the strange problem of my T60 making a feedback noise when my forearm, laid in front of the T60, was flexed a certain way. This had happened on two occasions in the last few days. When I Googled for "thinkpad t60 microphone", to make sure that the mic really was where I assumed it to be, the second site hit was "Fixing T60 Microphone Feedback Mute Problem."

I suspect that the root cause of the feedback is bad hardware or driver, and that it was triggered by my arm due to one of: (1) mechanical pressure on mic from the laptop case; (2) acoustic reflection into microphone; (3) bizarre RF interference.

In the Event of a Water Landing

Flight 1549 reconstruction video

Concept2 Arduino Project

After briefly considering making the Concept2 rowing ergometer more fun by hooking it up to Grand Theft Auto, I instead ordered an Arduino with the intent of hacking up some interval training aids and games that will run on the laptop.

Incidentally, the Concept2 Model B's shaft encoder unit appears to use a standard 2.5mm TS (2-conductor) plug. I decided not to try wiring the encoder to the laptop's microphone input, partly out of concern for my laptop, and partly because the Arduino gives more prototyping flexibility.