Thanks for those who helped me in my dc motor problem, esp. to hero, the tip32 worked great! it really did amplified the circuit.

Now i want to build a project for Christmas, its like a game or something. Well i would be using it at our Christmas party as part of the games we are preparing. I would like to make a two player game named "the price is right". Its a money detector or more on a color recognition circuit. Paper money here in the Philippines are a bit colorful. i would be using the 20, 50 and 100 peso bills (color orange, red and violet(or some bluish) respectively in color) in my game. the thing is if i show them an item the would insert the money through the detector depending on how the item costs. just like that, to make it simple, yes its a money color detector or recognition.

the bad news is i dont know where exactly to start. please help me

 

Use coloured filters (to be found in good photo shops) to find out any colour, e.g. to "see" red the sensor (photodiode, phototransistor or LDR) must have a filter of that colour. Adjust sensitivity according to the sensor you apply.

 

hmm, but what if it needs to see 3 colors? hmm and what does a color filter looks like? hehe so many questions, and another thing do i really need an op amp ckt for this project? waaaaa Christmas party is going near! please help me, cant start even from a scratch

 

Use three coloured filters - they look like a piece of transparent coloured plastic.

Opamps would be pretty well essential, and would probably make it a lort simpler.

A few days before you need it isn't a good place to start!.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

ADJD-S312 colour sensor from Avago works great. I have used this device and had very good results. My Device used white LEDs for a light source.

 

Very interesting, in the web page it said the chip could be embedded into digital phones,,,why????

 

I also wondered how useful it would be in a 'phone. It's probably part of the marketing liturgy

 

A bit of research turned this up :-
"illumination sensing for display backlight
adjustment such as colors, contrast and brightness
enhancement in mobile devices which demand higher package integration, small footprint and low power
consumption."

 

the way that i think would be best would be to have a red a blue and a green led and a cds cell then with a micro contoler flash the red led and mesure how much red is reflected then the blue then the green then use the difrent amounts to calculate the overall colour

 

Of course the red, green, yellow and blue can themselves be turned into sensors. Maybe this would be another way.