This module is designed to switch on/off a set of Ultra Bright LEDs suitable for a model helicopter by using a spare channel on the receiver (usually the undercarriage toggle switch). The power is supplied by the RC receiver (5.2v if you use a higher voltage you will have to limit it to 5.5v for the PIC) the current doesn't exceed 100mA, around 20mA when off. The LEDs were a problem, the ones I used are made by Kingbright needed 4v forward voltage except the Red ones which need 2.5v - so I used a limiting resistor to restrict the current. The circuit is a constant current source, published in the Elektor Magazine (July/August 2010 page 45), controlled by an output from the PIC, I have modified it to allow 5 LEDs to be used from a 5.2v source.	Component List PIC16F628 BC547B NPN Transistor ZVN4306A MOSFET N 47k resistor 6ohm resistor 39k resistor Red,Green,White Ultrabright LEDs Servo lead ABS Box Strip Board
	The internal oscillator is used in the PIC hence no external oscillator is needed. Constant current = 0.6v/R2
Basic Program written in the Proton Basic Language. '**************************************************************** * Name : RC-Lights.BAS * * Author :  * * Notice : Copyright (c) 2010 Mr D.Murrell * * : All Rights Reserved * * Date : 04/08/2010 * * Version : 1.0 * * Notes : Internal oscillator 4Mhz, input = PortB.0 * * : output = PortB.4 * **************************************************************** Device 16F628 REMINDERS = off Config INTRC_OSC_NOCLKOUT, CP_OFF, WDT_OFF, MCLRE_OFF, LVP_OFF, PWRTE_ON, DATA_CP_OFF, BODEN_ON REMINDERS = On XTAL = 4 WATCHDOG = false ALL_DIGITAL = True PORTB_PULLUPS = On ' Enable PortB pull-up resistors Setup: Dim RCPulse As Byte, Temp As Byte Declare RSOUT_PIN PORTA.1 TRISB=0 ;PortB=outputs, Pulsein changes state of pin.0 to input DelayMS 500 Main: RCPulse = Pulsein PORTB.0, High If RCPulse >170 Then PORTB.4 = 1 Else PORTB.4 = 0 EndIf ;RSOut Dec RCPulse GoTo Main	ZVN4306A pinout BBC547B pinout
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