Send sound using laser

[audioguru]

and what do you recoment to comunicate wireless?? please without RF

Wireless headsets use a modulated infrared beam for very high quality stereo.
Lights don't affect them much.
They use ordinary parts and the schematics are on the internet.

 

[anthony123]

how put in google??
Thanks anticipates...

 

[audioguru]

how put in google??

In Google I entered Infrared Headphones Circuit and got some that don't work, some that were very old and used parts that are not made anymore and ads for you to buy them.

There are two circuits that use a CD4046 phase-locked-loop IC for FM modulation of a high frequency. One uses an old RCA amplifier IC that is not made anymore but it can be made with transistors, and the other uses Cmos inverters connected as "linear" amplifiers instead of opamps.

 

[anthony123]

Well i gonna search and later i tall you...

 

[anthony123]

are you talking about this??
**broken link removed**

 

[audioguru]

The IR FM receiver circuit you linked to should work pretty well if you replace its cbsolete old CA3237 with a dual high speed opamp. A TL072 might provide enough gain and output for a stereo receiver with one channel at about 60kHz and the other channel at 120kHz. Then I think the transmitter and receiver for each channel must be completely separate.

It will work with a bright IR LED and an IR photo-diode (with a black lens). If they are a visible light laser pointer and a light sensitive photo-diode then it probably won't work in daylight.

How will you focus the laser from the CD? I hope you don't burn your eyes.

 

[anthony123]

well audioguru you let me in the same place: i only undertood the first text...
... with the CD laser diode i was very, extremy careful.. it burm everthing that touch.. i prefer keed under my box of trash...

 

[audioguru]

I am sorry that I speak in geek-talk technical language!

 

[anthony123]

i'm sorry too.. but the things is that i got to choice a diagram... wich one???

 

[audioguru]

Make the very simple first circuit. Then you will hear its noise and distortion and see how short is its range.
Make the complicated one if you want it better.

 

[anthony123]

but what do we do with the obsolet IC??? please helpme with to change it...

 

[audioguru]

but what do we do with the obsolet IC??? please helpme with to change it...

Just re-design it with a dual amplifier made with a TL072 dual opamp.

 

[anthony123]

well i gonna to repair the dising and more later i post it... thaks audioguru...

 

[anthony123]

But audioguro i have a doubt... how i conet the opamp??

 

[audioguru]

But audioguro i have a doubt... how i conet the opamp??

Just connect each opamp in a TL072 as an AC amplifier. Its minimum supply voltage is 7V. At 100kHz each opamp can have a gain of 32. Then the total gain is 1024.

 

[anthony123]

ok.. i will try change the schematics... i will, post later.. i'm busy rigth now.. Bye..