help for implement a transciever

[chaththa19]

hi,

I want to create a transmitter which transmit light signal when a electrical signal is given.im hoping to use a laser drive....is there any cheap laser drives?

 

[duffy]

I have a cigarette lighter with a built-in laser pointer I picked up for $3 at a gas station. If you can find one of those, try modulating the power with a drive transistor.

 

[john franklin]

RE laser transmitter



Its worth noting that the laser or led output will not be linear with the applied current. I suggest you use an fm or pulse length modulation system to get any kind of decent results from whatever you do decide on as a emitter and receiver
(The receiver/detector is also unlikely to be very linear !.)

best of luck! JOHN F

 

[chaththa19]

hey JOHN F,
i built a laser transeiver circuit which i found on http://www.geocities.com/SiliconValley/ which transmit RS232 output of a PC. still i didnt test it though...may be tommorrow..i need to go for a higher speed of data stream cos i wish to send a 2Mbps data stream through a fiber cable...i think what u have told is important to me but i didnt understand it well.can u explain bit light what uv told?..pls..pls..
Thankz

 

[chaththa19]

hi duffy,
thankz alot....i got one for 0.75$...what is a driver transistor?im very new to optical communication and electronics..but i love them..

 

[duffy]

A drive transistor would be like this MPSA06 -
**broken link removed**
- where they are driving it with a port pin.

Easier still, here's an "instructables" where they send music over a laser module like the one in the lighter just using a transformer and no drive transistors.
Send Music over a Laser Beam

It also shows has a very simple recieve circuit -
**broken link removed**

 

[chaththa19]

duffy thanks