TX 433Mhz arduino test

// ask_transmit
//DATA NANO D12
#include <RH_ASK.h>
#include <SPI.h> // Not actually used but needed to compile

RH_ASK driver;//Instancia Driver RH_ASK

uint8_t cnt=0;
String mensaje="TX";

void Debug(char*  txt){
  if (Serial){
     Serial.println (txt);
  }
}

void setup()
{
    if (Serial)
        {Serial.begin(9600);}  // Debug RS232
      else {while (true){};}

    if (!driver.init()){
         Debug("TX problem !!!");
    }else { Debug ("TX inicializado ");}

}

void loop()
{

    const char *msg = mensaje.c_str() ;//Mensaje de base
    String num=String (cnt+'\0');
    const char *msg2=num.c_str()+'\0';//Contador

    //strcat(msg,msg2);
    driver.send((uint8_t *)msg, strlen(msg)+1);
    driver.waitPacketSent();
    delay(1000);
    driver.send((uint8_t *)msg2, strlen(msg2)+1);
    driver.waitPacketSent();
    cnt+=1;
    Debug (msg);
    delay(2000);
}