const unsigned long eventInterval_1 = 1;
const unsigned long eventInterval_2 = 76;
const unsigned long eventInterval_3 = 151;
 
int LED_1 = 10;     //Bias resistor isolation relay
int LED_2 = 11;     //Antenna changeover relay (RF OUTPUT)
int LED_3 = 12;     //Antenna changeover relay (RF INPUT)
int LED_4 = 13;     //Filament xfrmr soft start resistor (OUT) relay
 
unsigned long previousTime_1 = 0;
unsigned long previousTime_2 = 0;
unsigned long previousTime_3 = 0;

const int BUTTON = 7;
int BUTTONstate = 0;
 
void setup() 
{
  Serial.begin(9600);
  pinMode(LED_1,OUTPUT);
  pinMode(LED_2,OUTPUT); 
  pinMode(LED_3,OUTPUT);
  pinMode(LED_4,OUTPUT); 
  pinMode(BUTTON, INPUT);   // PTT Close
}
 
void loop() 
{
  BUTTONstate = digitalRead(BUTTON);
  if (BUTTONstate == HIGH)
  {PTT_C();}
  else
  {PTT_O();}
}  


void PTT_C()
{ 
  unsigned long currentTime = millis();
  if (currentTime - previousTime_1 >= eventInterval_1)
  {
  digitalWrite(LED_1,HIGH);
  previousTime_1 = currentTime;
  }
  else if (currentTime - previousTime_2 >= eventInterval_2)
  {
   digitalWrite(LED_2,HIGH);
   previousTime_2 = currentTime;
  }
  else if (currentTime - previousTime_3 >= eventInterval_3)
  {
   digitalWrite(LED_3,HIGH);
   previousTime_3 = currentTime;
  }
}

void PTT_O()
{ 
  unsigned long currentTime = millis();
  if (currentTime - previousTime_3 >= eventInterval_1)
  {
   digitalWrite(LED_3,LOW);
   previousTime_3 = currentTime;
  } 
  else if (currentTime - previousTime_2 >= eventInterval_2)
  {
   digitalWrite(LED_2,LOW);
   previousTime_2 = currentTime;
  }  
  else if (currentTime - previousTime_1 >= eventInterval_3)
  {
  digitalWrite(LED_1,LOW);
  previousTime_1 = currentTime;
  }


}