55 Minute Alias

This video demonstrates an aliased frequency (minute hand) reflected across the Nyquist limit of the sampling rate. A second frequency is within the limit (the hour hand).

There's also a car chase.

More info at http://burtonmackenzie.com/2006/07/i-cant-drive-55.html

Category:

Science & Technology

Tags:

• alias
• aliasing
• frequency
• clock
• nyquist
• toy
• car
• chase
• burton
• mackenzie

[jo13ck]

can you explain why the minute hand appears to be moving backward and the hour hand appears to be moving forward?

[MacKenzie]

You can demonstrate this effect for yourself - set the clock to some arbitrary time and take a picture (or just note where the hands are), then move the time *ahead* 55 minutes. Compare the hand positions with the previous photo and you'll see the hour hand moves forward and the minute hand appears to move backward.

[onnozen]

I think it's "Next is the E" by Moby, or a remix of that song.

[hlentzw]

just sample every 55 minutes

[consistsofthree]

hey does anyone have an ID on this song?

[tymill]

cool. Did you really wake up each hour to move the cars a tiny bit?? Commitment!