Current Part:
Direct TV RC24 Remote
IR Phototransistor
10kΩ Resistor
1kΩ Resistor
1MΩ Resistor
5kΩ Trimpot
4x 330Ω Resistor
4.7uF Capacitor
4x LEDs
LM741 Op Amp
16x2 LCD Screen
Breadboard
Wires
Parts List Details
For those of you not familiar with all the parts listed out above, I'll quickly describe the purpose of a few of the key parts below. The parts list above includes links to where you can find & purchase the parts used in this tutorial if you need them.
PIC 18F452
The PIC 18F452 is the microcontroller used in this project. The specific functionality that it offers us is the CCP module, capture and compare. This module can detect rising and falling edges on signals. Since the IR receiver built in this tutorial will be looking for these in the data signal, it's a perfect match for this tutorial's design.
Direct TV RC24 Remote Control
There's really no good reason that I chose this remote control for the tutorial. My neighbor was going to throw it out, so I took it off her hands. All IR remote controls work in a very similar and so it's just a matter of looking closely at the transmitted signals and decoding them.
IR Phototransistor
This is the device that we will use in the infrared receiver to capture the transmitted signal, and pass it along to the microcontroller. The phototransistor acts like a normal transistor switching on and off depending upon the intesity of IR light being shined at it.
Breadboard
The breadboard is used to build the IR receiver circuit and accompanying IR amplifier circuit. The IR amplifier circuit both amplifies and inverts the signal into a more familiar +5v = '1' and +0v = '0' stream of digital data.
LM741 Op Amp
This is the amplifier used to invert the received IR signal and to amplify the signal making sure it stays at either +5v or +0v depending on the current data being transmitted.
Wires & Resistors
The wire is used to connect all the parts together. Wire-wrap may also be used for connecting the 16x2 LCD to the PIC. The resistors all have specific purposes, some are for protecting LEDs, others for setting the amplification factor for the op-amp. The 5k trim-pot connected to the LCD is used to set the contrast of the 16x2 LCD.