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Member Since Aug 23rd, 2007

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Recent Comments:

The Bill Day giveaway (part 1) - Toshiba Gigabeat T400

Jun 27th 2008 9:24PM You can't beat Sidewinder gamepad. Ahh the memories with that device.

The Bill Day giveaway (part 2) - Office Ultimate 2007

Jun 27th 2008 9:23PM GO DOS! I love using "cmd" even now on Windows XP.

The Bill Day giveaway (part 4) - Windows Vista Ultimate

Jun 27th 2008 9:20PM I love Windows XP. Too bad it's going the way of the dinosaurs.

The Bill Day giveaway (part 3) - Zune 80GB (black)

Jun 27th 2008 9:19PM I loved the Sidewinder, circa 1997? It had that "twist" for that extra axis when controlling mechs in Mechwarrior 3. Speaking of which, that wasn't a bad Microsoft product neither.

Win a Philips 42PFL5603D 42-inch 1080p HDTV!

Feb 5th 2008 8:44PM That's a sweet looking TV.

Win an LCD HDTV, Xbox 360, and plenty of Old Spice

Feb 5th 2008 8:41PM Me want big TV.

Bioshock Tuesday: win an Xbox 360 and a copy of Bioshock

Aug 26th 2007 10:45AM The original Quake.

-J

DIY laser long-distance listening device

Aug 23rd 2007 7:42AM Actually I made one of these in college. Using an ultra sensitive photo transistor, cascaded amplifiers and voice-band filter. I am skeptical of the results in this particular set up. The linear region of the photocell is very small, and to detected amplitude change, the photocell needs to operate at the linear region. With a laser, the photocell will either saturate when the beam hits it directly, or it will not detect light at all. In addition, there was no pre-amp for the photocell, with means the change in the induction of current into microphone jack would be in the millivolt range (and that's on a good day, probably in the sub-millivolt range). Add in the noise from a 2 feet unshielded audio cable and you won’t hear anything. Not to mention, the natural harmonics of the window itself would be unfiltered (more noise), as well as vibrations to the laser and the receiver. These factors would be more than ample to flood out the vibration from the voice.

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