http://www.geocities.com/siliconvall...7156/laser.htm

i found the above link.
i want to build it...

i think there some problems how can i fix them??

1. The distance between "Laser transmitter circuit" and "CPU serial Port" is about 10 meters. If we use a simple wire the output signal of CPU serial Port will be distorted... it will not reach to Laser transmitter circuit in the same shape as it was transmitted.
How can i fix this problem.

2. Same problem in receiver side..

Some may say that decrease the speed of transmittion but i don't want to decrease..

Easy and cheap solution please..

 

10 meters isn't a problem for rs232 ... but as you say, using a simple wire, that may be your problem.

use category 5 cable (cheap and easy to come by), you should have no problems.

or better yet, see if you can find some old shielded serial cable (check with factories, banks or grocery stores) ... they should have piles of it crammed in some room with their old serial terminals after upgrading to ethernet or wireless.

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If you don't have a planet, what good are gold bars?

want to contact me directly? gmail gordonthree
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$69 for a red laser is way too expensive, knowing that I could get a GREEN one for @ $50, that goes even farther. Check this site out: www.amazing1.com

 

a green laser doesn't go any further than a red laser.

green has the advantage of being at the peak of human visual sensitivity ... so your eye can see the green dot reflected from a much greater distance.

green pointers are also usually much more powerful than red, compare the measured emissions (mW).

__________________
If you don't have a planet, what good are gold bars?

want to contact me directly? gmail gordonthree
check out my project website: http://projects.dimension-x.net
Favorite numbers:
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0

 

I also want to know, will this circuit work in sunlight??
What will happen when sunlight will through on Photo-transistor???

 

You place the photo-transistor in a tube to prevent sunlight hitting it.

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