I don't have any experience using Arduino kit, and we have this project where we have to develop an optocoupler using a red LED, photosensor, and a potentiometer. We have to use the Arduino board as a 5v power supply in our circuit. I need any help I can get ASAP.
Which photosensor? Post a datasheet. What does the potentiometer do? Surely you were given more information on the requirements of the assignment. Please share those requirements.
A Google search for "diy optocoupler" turns up pages like this one.
Hi asm4real,
You can make an opto-coupler by holding an LED and a phototransistor face to face with a bit of heat shrink tubing. Make the sending circuit by wiring the cathode of the LED to a 300-1000 ohm resistor then a switch, then to ground. Power the anode by attaching it to a + 5 volt source (could be a battery, could be the 5 volt output of your Arduino.) Be sure the ground the switch is hooked to is the same ground of the power supply (battery or Arduino.)
Make the receiving circuit by wiring a (could be different) 5 volt source to the collector of the photo-transistor, then the emitter to a 1K resistor, then to one side of the potentiometer. Wire the center of the pot to ground (again it could be a different ground than used by the sending circuit.)
Finally, wire the place the transistor and the resistor connect to an Arduino input pin. Write some code, so that you can adjust the pot to a point where when you switch the LED on and off, the pin goes HIGH and LOW.
Boom, you are done!
ps, coding is left as an exercise for the student.
This diagram:
is on page 45 of this book:
AsM4Real:
we have this project where we have to develop an optocoupler using a red LED, photosensor, and a potentiometer.
Do you mean that your teacher expects you to build something that s/he never taught you anything about? That seems unlikely.
...R
ChrisTenone:
This diagram:
is on page 45 of this book:
I have that book, too. Somewhere?
Paul
AsM4Real:
I don't have any experience using Arduino kit, and we have this project where we have to develop an optocoupler using a red LED, photosensor, and a potentiometer. We have to use the Arduino board as a 5v power supply in our circuit. I need any help I can get ASAP.
I think that you might be able to use 2 ordinary LED's, arranged just like Forrest Mimms pictured.
As for the book, I consider them more like booklets...
I have the 555 and some of the others.
I think my 555 is pre-1983..
makes me want to dust one off...
...just remember not to use the clear heat-shrink.