Project5.Digital IR Transmitters
==================================

Description
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IR transmitter module is designed for IR communication, which is widely used for
operating the television device from a short line-of-sight distance. Since 
infrared (IR) remote control uses light, it requires line of sight to operate 
the destination device. The signal can, however, be reflected by mirrors, just 
like any other light sources. Infrared receivers also tend to have a more or 
less limited operating angle, which mainly depends on the optical characteristics 
of the phototransistor. However, it’s easy to increase the operating angle 
using a matte transparent object in front of the receiver.


Specification
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- Power Supply: 3-5V
- Infrared center frequency: 850nm-940nm
- Infrared emission angle: about 20 degrees
- Infrared emission distance: about 1.3m (5V 38Khz)
- Interface socket: JST PH2.0
- Mounting hole: inner diameter is 3.2mm, spacing is 15mm

Connect
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.. image:: /img/connect/5_bb.png

Code
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.. code-block:: c
    
    int led = 3;
    void setup() {                
    pinMode(led, OUTPUT);     
    }
    void loop() {
    digitalWrite(led, HIGH);  

    delay(1000);               
    digitalWrite(led, LOW);   
    delay(1000); }

In the darkness of the environment, you are going to see blinking blue light on 
phone’s screen when using camera to shoot the infrared LED. Upload well the above 
code to the board, the led on the sensor will blink red light. 

Phenomenon
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.. image:: /img/phenomenon/5.jpg