Tuesday, January 17, 2006
Tuesday Bike Blogging Returns
This is Amber's bike:
She bought it on eBay a few years ago. It arrived in a large box at her dorm.
This is on the top of the seat:
She bought it on eBay a few years ago. It arrived in a large box at her dorm.
This is on the top of the seat:
Thursday, January 05, 2006
States I've Visited
I was reminded of this via Milligan:
(Courtesy of World66)
I'm cheating a bit, as I'm including states in which I've only stopped in an airport (Florida, New Jersey) and states I've only traveled through via train (Colorado, Kansas) or car (Ohio, West Virginia).
Places to go: New England, the South, Big Sky Country.
(Courtesy of World66)
I'm cheating a bit, as I'm including states in which I've only stopped in an airport (Florida, New Jersey) and states I've only traveled through via train (Colorado, Kansas) or car (Ohio, West Virginia).
Places to go: New England, the South, Big Sky Country.
Monday, January 02, 2006
Happy Leap Second
Steven and I recorded the leap second last night. The recording itself was via Audacity, was hastily put together, and produced only a mediocre, noisy signal. We got about 5 minutes of raw data: mp3 ogg. The recording itself was pretty basic, mostly because I don't actually know how to do sound recording.
I do know a little bit (emphasis on the "little") about processing. There is a bit of junk at the beginning and end of the raw recording due to us moving the shortwave reciever around and trying to find the best signal. After I cut that off, I used SoX to apply a "Sinc-windowed" lowpass filter. One of the minute pulses (I think the one on the hour) is at 1000 Hz, so that puts a lower bound on the 6dB corner of the filter. I played around with a couple of different values for that, and didn't notice too big a difference. I settled on 1100 Hz. SoX also has a Butterworth bandpass filter, and a logarithmic bandpass filter. The Sinc-windowed filter sounded the best, so I kept that. The final commands were:
sox leap-short.ogg leapsecond-final.ogg filter 0-1100 for the ogg, and
sox leap-short.mp3 leapsecond-final.mp3 filter 0-1100 for the mp3
Here is the final result: ogg mp3
Finally, Steven tells me that John Ackermann has done a better job of this than we did.
I do know a little bit (emphasis on the "little") about processing. There is a bit of junk at the beginning and end of the raw recording due to us moving the shortwave reciever around and trying to find the best signal. After I cut that off, I used SoX to apply a "Sinc-windowed" lowpass filter. One of the minute pulses (I think the one on the hour) is at 1000 Hz, so that puts a lower bound on the 6dB corner of the filter. I played around with a couple of different values for that, and didn't notice too big a difference. I settled on 1100 Hz. SoX also has a Butterworth bandpass filter, and a logarithmic bandpass filter. The Sinc-windowed filter sounded the best, so I kept that. The final commands were:
sox leap-short.ogg leapsecond-final.ogg filter 0-1100 for the ogg, and
sox leap-short.mp3 leapsecond-final.mp3 filter 0-1100 for the mp3
Here is the final result: ogg mp3
Finally, Steven tells me that John Ackermann has done a better job of this than we did.
