infrared transmitter and receiver problem

[a.s.zidan]

Hello, I'm looking for very simple plans/schematics for an infrared transmitter and receiver for small distances and avoid problem of work on daylight as the sun has infrared so if circuit output is led it shine in daylight and don't switched of when put an obstacle between the transmitter and receiver .
afriend tell me can use modulated transmitting & receiving. are this true.
plz if anyone had some available or could point me in the right direction.
Any help would be appreciated - Thanks!

 

[stdee]

using IR is not easy in direct sunlight
what distance do you want ?
and what are you transmitting ? audio~ video ?

 

[a.s.zidan]

i should use IR
very small (face to face)
ir led

 

[jpanhalt]

Are you willing to use a microcontroller? I have a design based on the 12F509 that detects at a distance of 2 to 3 inches or so in bright sunlight.

John

 

[a.s.zidan]

no using simple circuit from tr. r c . .....

 

[jpanhalt]

At a minimum, you will need to use a modulated tx and matching receiver. I think it would be very difficult to do without that. If you want to try anyway, put the rx at the end of a 1 to 3" tube and aim carefully at each other.

John

 

[a.s.zidan]

At a minimum, you will need to use a modulated tx and matching receiver. I think it would be very difficult to do without that.

John

ok can u get schematics for these modulated tx and matched rx

thanks

 

[jpanhalt]

Just look up your favorite vendor. Vishay is one. Check out its IR emitter and detector modules, such as this one. You can use a 555 or 556 to get the correct modulation for the emitter.

John

 

[stdee]

here Simple IR audio link

and here IR Headset

 

[stdee]

I have posted two links to very simple ccts, just waiting for mod to approve posting of the links

 

[kakin]

What you can do is drive the transmitter led with a basic oscillator, and the receiving led just like if it was direct on/off but decoupled and smoothed with a capacitor, after that a simple schmitt trigger can be used to get it back to digital compatible on/off.

 

[abicash]

Hello

Why is there a need of sensing IR in your project?
You can work on visible light intensity alone.

 

[a.s.zidan]

hi guys i want to modify this circuit to avoid sun light

**broken link removed**

Section 2 -
Infrared Light Photo-Detector Circuit
Basic Phototransistor Detector

 

[MikeMl]

Previous Threads which deal with using an IR detector in bright sunlight:
https://www.electro-tech-online.com/threads/bpw41n-problem.97725/
https://www.electro-tech-online.com/threads/555-timer-for-ic-transmitter-error.98188/
https://www.electro-tech-online.com/threads/ir-beam-break-detector.97461/

 

[stdee]

what are you trying to do with the cct ? detect a toy train as shown on the link to section 2 ?

if so just mount the diode and tranny in a separate long dark tube each side of the track with a red filter over the end

 

[shimaemad]

ir reciver and transmitter