Fun little project at GB5BRA Banbury Show

The Banbury Amateur Radio Society will be at the annual Banbury show on Sunday 8th June. We will be operating a station GB5BRA and look forward to contacting you...

Also at the show we will be promoting amateur radio. For this we have a display panel "LEARN _ BUILD _ PLAY". And a tiny demo using an Arduino to send an automated morse message "CQ CQ CQ DE GB5BRA GB5BRA K".

Circuit

Here's the code:

// Morse transmitter, with oscillator 
// LED & OSC Pin 7

// output pin
#define LEDPIN 7

// text array codes
#define DOT 0
#define DASH 1
#define SPACE 2
#define WORD 3

// message words
int CQ[] = {1,0,1,0,2,1,1,0,1,3};
int DE[] = {1,0,0,2,0,3};
int GB5BRA[] = {1,1,0,2,1,0,0,0,2,0,0,0,0,0,2,1,0,0,0,2,0,1,0,2,0,1,3};
int K[] = {1,0,1,3};

// dash = 3 dots, space = 3 dots, word = 7 dots
#define DOTTIME 150

void setup() 
{
  pinMode(LEDPIN, OUTPUT);
}

void loop() 
{

// send message words, sends CQ CQ CQ DE GB5BRA GB5BRA K
  sender(CQ);
  sender(CQ);
  sender(CQ);
  sender(DE);
  sender(GB5BRA);
  sender(GB5BRA);
  sender(K);
  
  delay(2000); // repeat after 2 secs
}

// send a word
void sender(int dida[]) {

  int x = 0; // array index

// send characters up to end of word
  while(dida[x] != WORD) {
   switch (dida[x]) {
    case DOT:
       transmit(DOTTIME);
       delay(DOTTIME); // add after dot
       break;
    case DASH:
        transmit(3 * DOTTIME);
        delay(DOTTIME); // add after dash
        break;
    case SPACE:
         delay(2 * DOTTIME);  // add for space
         break;
    }
    x++;
  }
  delay(6 * DOTTIME); // add   for word
}

// transmit for time (msec)
void transmit(long time) {

  digitalWrite(LEDPIN, HIGH); // turn on LED
  delay(time); // time 
  digitalWrite(LEDPIN, LOW); // turn off LED
}

Update: Its a pity but the Banbury Show, where the project would be shown, was cancelled 3 days before it was due, because of a water logged field.