Date: Sat, 27 Aug 2011 09:50:15

Author: Steve Wonnell

Subject: Re: Fall Quarter Demo Show Ideas Needed

Post:


Sounds like a great variation for the 1H10.35 "bend the wall" demo ...


On Thu, 25 Aug 2011, Dan Beeker wrote:

> Date: Thu, 25 Aug 2011 12:12:20 -0400
> From: Dan Beeker
> Reply-To: tap-l@lists.ncsu.edu
> To: tap-l@lists.ncsu.edu
> Subject: Re: [tap-l] Fall Quarter Demo Show Ideas Needed
>
> You don't even need an interferometer. Just use a photodiode and set the reflected beam up so
> the edge of the beam movers half of the diode. As the beam moves in and out of the diode's view
> it amplitude modulates the diode current. Monitoring conference room conversations by reflecting
> a beam off a window is a tried and true industrial espionage technique. Many companies will put
> white noise generators on their windows to combat this problem. For really sensitive information
> you meet in an internal room that has no windows. Electronic bugs are a different matter.
>
> Dan Beeker
>
> On 8/25/11 11:34 AM, Adam Beehler wrote:
> I have tried this and it indeed can work, just in case you were curious.
> Adam Beehler
>
> On 8/25/2011 5:39 AM, Ann Reagan wrote:
> Paul -
>
>
> Have you tried to get voice signal by shining the interferometer off of
> a window pane? I would like to have my 2nd year engineering students
> try this with as little coaching as possible.
>
>
> Ann R.
>
>
>
>
> Date: Wed, 24 Aug 2011 16:19:43 -0500
> From: Paul Nord
> To: tap-l@lists.ncsu.edu
> Cc: Paul Nord
> Subject: Re: Fall Quarter Demo Show Ideas Needed
> Message-ID:<5D679CAC-1BCD-42D6-AE1C-6480EFB69E2A@valpo.edu>
>
> Don't forget the simple interferometer shining into a solar cell
> attached to a speaker/amp.
> On the tabletop, setup a laser pointer, beam splitter, mirror, and the
> solar cell to form an interferometer. The alignment is pretty simple.
> Just make sure that the mirror shines laser directly back on itself.
> The solar cell will simply be set to receive the light from the beam
> splitter. Subtile changes in the path length (vibrations in the table,
> air currents, changes in the table's shape from pressing on it) can be
> "heard" has the interference fringes pass over the solar cell. It's a
> creepy sound. It picked up me stomping my foot from the back of the
> room.
>
> Paul
>
>
>
> Dr. Ann M. Reagan
> Adjunct Faculty
> Department of Math/Physics/Engineering
> College of Southern Maryland, Leonardtown Campus
>
>
>
>
> --
> Dan Beeker
>
>


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