how to send text over rf ?

hello arduino friends.

i am trying to make two arduino based devices that sends text one to an other !
until now everything is ok !

i have a 4x4 keypad and a 16x2 lcd connected and they both work fine !

the input method is like a normal sms creation, a few presses over a keypad changes the character on the lcd and if the time between the two presses is more that 1 seccond it moves the cursor to the next step !

how can i send those chars over rf ?
and are there any schematics that i can download to test ?

#include <Time.h>
#include <Keypad.h>
#include <ctype.h>
#include <MorseEnDecoder.h>
// include the library code:
#include <LiquidCrystal.h>

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
const byte ROWS = 4; //four rows
const byte COLS = 4; //three columns
// Define the keymaps.  The blank spot (lower left) is the space character.
char alphaKeys[ROWS][COLS] = {
  {'a','d','g','A'},
  {'j','m','p','B'},
  {'s','v','y','C'},
  {' ','.',',','D'}
};

char numberKeys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {' ','0','.','D'}
};

boolean alpha = false;   // Start with the numeric keypad.
char* keypadMap = (alpha == true) ? makeKeymap(alphaKeys) : makeKeymap(numberKeys);

byte rowPins[ROWS] = {
  45, 47, 49, 51}; 	//connect to the row pinouts of the keypad
byte colPins[COLS] = {
  37, 39, 41, 43}; 	//connect to the column pinouts of the keypad

//create a new Keypad
Keypad keypad = Keypad(keypadMap, rowPins, colPins, sizeof(rowPins), sizeof(colPins));

unsigned long startTime;
const byte ledPin = 13;	 
int i = -1;
int j = 0;
int k=0;
long puss=0;
long puss2=1;
int flag=0;
int flag2=1;
int flag3=0;
int functionKey = 0;
String messageComplete[34];
char message1[ ] = "                ";
char message[ ] = "                ";
int morseOutPin = 13;
int morseInPin = 7;
char temp;
morseDecoder morseInput(morseInPin, MORSE_KEYER, MORSE_ACTIVE_LOW);
morseEncoder morseOutput(morseOutPin);


void setup(){
  lcd.begin(16, 2); // Starts the LCD library and sets 2 coloumns of 16 chars each
  Serial.begin(9600); // begins the serial communication over usb with the computer at 9600 bauds
  pinMode(ledPin, OUTPUT); // sets the led on the arduino as an output device
  digitalWrite(ledPin, LOW);                                                // Turns the LED on.
  keypad.addEventListener(keypadEvent);                                      // Add an event listener.
  keypad.setHoldTime(500);
  morseInput.setspeed(64); // sets the input to 64 chars per minute
  morseOutput.setspeed(64); // sets the output to 64 chars per minute
};

void loop(){
  char key = keypad.getKey();
  if (alpha && millis()-startTime>100) {           // Flash the LED if we are using the letter keymap.
    digitalWrite(ledPin,!digitalRead(ledPin));
    startTime = millis();
  }
};
//transmition protocol
void transmit(){

}

// Take care of some special events.
void keypadEvent(KeypadEvent key) {
  static char virtKey = NO_KEY;      // Stores the last virtual key press. (Alpha keys only)
  static char physKey = NO_KEY;      // Stores the last physical key press. (Alpha keys only)
  static char buildStr[12];
  static byte buildCount;
  static byte pressCount;
  switch (keypad.getState())
  {
  case PRESSED:
    if (flag2==0 & isalpha(key)) {              // Pressed the same key again...
      puss=millis();
      if (puss != puss2){
        if ((puss - puss2)>1000){
          flag3=1;
        } 
        else {
          flag3=0;
        }
        puss2=millis();
      }

    }
    if (isalpha(key)) {          // This is a letter key so we're using the letter keymap.
      if (physKey != key) {        // New key so start with the first of 3 characters.
        pressCount = 0;
        virtKey = key;
        physKey = key;
        flag2 = 1;
      }
      else {              // Pressed the same key again...
        if (flag3==1){
          virtKey++;               // so select the next character on that key.
          pressCount++;            // Tracks how many times we press the same key.
          flag2 = 0;
          flag = 0;
        } 
        else {
          virtKey++;               // so select the next character on that key.
          pressCount++;            // Tracks how many times we press the same key.
          i--;
          flag2 = 0;
          flag=1;
        }
      }
    }

    if (pressCount > 2) {        // Last character reached so cycle back to start.
      pressCount = 0;
      virtKey = key;
    }

    if (isdigit(key) || key == ' ' || key == '.' || key == ',') {
      virtKey = key ;
    }
    if (key == 'A'){
      key = 'A';
      functionKey = 1;
    }
      if (key == 'C'){
      functionKey = 1;
      lcd.begin(16, 2);
      i=0;
      j=0;
      i--;
      i--;
      virtKey = 'C';
    }  
    if (key == 'D'){
      functionKey = 1;
      virtKey= 'D';
      if (i<0 & j==1){
        i=16;
        j=0;
      }
      lcd.setCursor(i,j);
      lcd.print(" ");
      lcd.print(" ");
      i--;
      i--;
    }
    if (i > 14  & j == 0){ 
      i = -1;
      j = 1;
    } else if (i == 15 & j == 1){
      i = -1;
      j = 0;
    }
    else {
      i++;
    }
//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    lcd.setCursor(i,j);  // prosexe apo edo !!!!!!!!!!!!!!!!!!!!!!!
    if (functionKey == 0){
      lcd.print(virtKey);    // Used for testing.
      if (j==1){
       message1[i] = virtKey; 
      } else {
       message[i] = virtKey; 
      } 		// mexri edo !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    }
//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
//to message 1 einai i kato grammi tis lcd kai to message einai i epano 
// pos mporo na ta kano auta binary ?
break;

  case HOLD:
    if (key == 'B')  {      // Toggle between keymaps.
      virtKey='B';
      functionKey = 1;
      if (alpha == true)  {            // We are currently using a keymap with letters
        keypad.begin(*numberKeys);   // and want to change to numbers.
        alpha = false;
        digitalWrite(ledPin, LOW);
      }
      else  {                          // Or, we are currently using a keymap with numbers
        keypad.begin(*alphaKeys);    // and want to change to letters.
        alpha = true;
      }
    }
    break;

  case RELEASED:
    break;

  }  // end switch-case
}  // end keypad events

how can i send those chars over rf ?

VirtualWire and a cheap 3xx or 4xx MHz rx/TX pair.

i was more like thinking over vlf ! is there any sugestion over vlf ? schematics and code !

i was more like thinking over vlf !

Sorry, it is the mind-reader's day off.

OK, use VirtualWire and a COTS VLF tx/rx pair.

Got a VLF ham licence?

no i don't ! i am just experimenting !

hope noone hears about that !

:smiley: !

thanks for your time !