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Support Forum » Theremin Project.

April 12, 2011
by r91michael
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I am working on the Human Theremin tutorial. However I mounted the infrared photo transistor in block of wood and am going to be presenting the project for school. I have gotten everything wired up correctly as near as I can tell from the pictures of the website. I also have gotten the code loaded on the chip, however when i hook the battery up nothing happens. I am not quite sure what i am doing wrong. I was wondering if there was anyway to tell if my LEDs are bad? I have taken several different digital cameras to see if i could see them light up but i am not able to see anything. Any ideas? My project is due soon and i would like to get it working!

April 12, 2011
by missle3944
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Can you post a picture of your setup? Also check the wiring of the emmiter and the detector becuase on the tut page they said that the sides were switched on the ones that they bought.

-missle3944

April 12, 2011
by r91michael
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alt image text alt image text alt image text alt image text

April 12, 2011
by r91michael
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http://img13.imageshack.us/i/breadboard.jpg/

http://img845.imageshack.us/i/rightk.jpg/

http://img857.imageshack.us/i/leftjc.jpg/

http://img20.imageshack.us/i/entire.jpg/

Here are the links wasn't quite sure if the previous one had worked correctly. And yes I did check the wiring of the emmiter and detector and am fairly confident they are correct.

April 13, 2011
by missle3944
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Hi r91michael,

Did you test this on your breadboard first? Check your battery or use the nerdkits usb cable for power or use a power supply. I'm not to sure on the wiring because I'm not to experienced with that. It sounds like it is more of a power issue. I'd recheck the wiring on the MCU with the guide. Do you have the LCD hooked up or use some kind of indicator.

-missle3944

April 15, 2011
by BobaMosfet
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Questions-

What is the phototransistor (part #, so I can find a datasheet)? Normally, it's expecting you to shine infra-red light on it- what are you using to generate the infrared? What frequency (nanometers), as well?

Also, I don't think you've got it wired properly. I looked at your images, and you have essentially wired the components in both a parallel, AND a serial fashion so that your resistance values are reciprocal. I wasn't quite sure with the color, but it looked like both 100 Ohm and 1000 Ohm resistors were being used. Why did you choose those values?

Definitely work these things out on breadboard AFTER you've created a schematic.

As for seeing infrared, I use a NightVision Monocular to see LEDs to make sure they are on or not.

BM

April 15, 2011
by missle3944
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Coincidentally, I just went down to the shack to get some parts for this project and I got the wrong resistor values!!! I'll just have to go back tomorrow...

-missle3944

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