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Build Your Own Bluetooth Sniper Rifle
Jim Buzbee writes "I don't think I'd do it, but these guys built a Bluetooth Sniper rifle, went to the roof of a downtown Los Angles skyscraper and pointed it at nearby buildings. See what they found, and if you're so inclined, they'll show how to build your own and maybe, just maybe, you too can snag Paris Hilton's address book." (Which was not snagged via Bluetooth snooping, as the article points out.) This version looks a bit more polished than the one mentioned last August.
Fear not. Perfectly aligned in the EM wave sense does not equal correct alignment in the mass/bullet sense. One must adjust for windage, for one thing. For another, even if you could get the range via bluetooth, the parabollic trajectory of the bullet (some calibres are 'flatter' than others, and even different manufacturers) must be taken into account based on that range.
Image of the gun. Imo somebody could easily mistake that for a homebrew silencer on the end.
Your hair look like poop, Bob! - Wanker.
This article shows that "short range" RF technologies such as bluetooth or RFID are only short range in the context of a particular transceiver. If someone wants to access an RF device from a greater distance, they need only build a high-gain antenna.
Two wrongs don't make a right, but three lefts do.
Actually no.
You will hear a sonic boom anytime something travels faster than the speed of sound at your location. Typically, this means an aircraft must travel abut Mach 1.15 above you for you to hear the boom on the ground. An aircraft travelling Mach 1 will typically not produce a boom on the ground as the speed of sound is greater on the ground than it is at altitude. And, of course, anything travelling faster (i.e. Mach 4) will cause a boom as well.
Back to our program.
Don't say at least, ecause some sniper rifles are capable of much better performance, although they are very costly. For example, the Barrett M82A1 has an MOA of 1.5-2.0 or about 4.5"-6" drift at 300 yards. Additionally, the drift depends on the angle at which the rifle is fired, even if it is aimed directly at your phone. If you're shot at from above or below there will be an additional downwards component of the bullet's velocity working with the force of gravity causing the bullet to fall faster, whereas if you are up high and shot from below there will be an upwards component of the bullet's velocity working with gravity to decrease the drift of the bullet.
just a remiander (in the absence of air resistance, and bullets are designed for minimal air resistance)
Dy = 0.5(-32 ft/s/s)(Dt)^2 + v*sin(a)(Dt)
Dt = (Dx)/(v*cos(a))
so:
Dy = 0.5(-32 ft/s/s)((Dx)/(v*cos(a)) + (Dx)tan(a)
where:
a=angle
v=inital velocity
Dt= change in time
Dx= change in horizontal position
Dy= change in vertical position
therefore, if a is between 0 and 90 degrees there will be less drift than if a is between -90 and 0 degrees.