[IAEP] [Sugar-devel] Turn your frequency generator into a super powerful mosquito repeller

[Walter Bender]

On Fri, Jul 8, 2011 at 7:49 AM, Bert Freudenberg <bert at freudenbergs.de> wrote:
> On 08.07.2011, at 08:08, Caryl Bigenho wrote:
>
>> Hi....
>>
>> Let's put this to a test!
>>
>> With all the flooding we are having in Montana this summer the clouds of mosquitos are really fierce! Our family is visiting with their PCs and I have a Mac.  We can try this in the next couple of days and see if it really works. It says it can be barely audible. I was curious to see how low these notes would be and found this interesting chart (link below). Many of the instruments listed are no longer in daily use and exist mainly in museums, but some, such as the bass viol and bassoon are very common. In fact, my husband has his bassoon here with him in Montana!  But, I don't think he wants to play a continuous low note... he has better things to do! We can find an appropriate tone generator for our test.
>>
>> http://www.contrabass.com/pages/frequency.html
>>
>> Caryl
>
> Easy to test using an XO. In Etoys, select the "sound" category in any object's viewer, drag out the "play frequency of" tile, make the script ticking. You should hear the sound now, and you can click on the green down-arrow to lower the frequency:
>
>
>
>
> On my XO it becomes inaudible at 200 Hz using the built-in speakers. Plugging in good headphones it goes way below 30 Hz.
>
> - Bert -
>
>
>
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>

Absolutely we should use things like this as an opportunity for kids
to do some science. (FWIW, you can use Turtle Art to generate sine
waves as well, by importing a python block)

[[0, ["start", 2.0], 0, 100, [null, 1]],
[1, ["userdefined", "pysamples/sinewave.py"], 0, 142, [0, 2, null]],
[2, ["number", 100], 58, 142, [1, null]]]

Where you set number to whatever Hz you want.

-walter

-- 
Walter Bender
Sugar Labs
http://www.sugarlabs.org