Sender Script (by JaWs)

#include "RF24.h"
#include "SPI.h"
#include "nRF24L01.h"

RF24 radio(6, 7);
const byte addresses[][6] = {"ADDR1", "ADDR2"};

void setup() {
  Serial.begin(9600);
  // Serial.setTimeout(1000);
  radio.begin();
  radio.setAutoAck(true);
  radio.setPALevel(RF24_PA_LOW);
  radio.openWritingPipe(addresses[0]);
  radio.openReadingPipe(1, addresses[1]);
  radio.stopListening();
}

void sendData(String s) {
  radio.stopListening();
  delay(50);
  Serial.print("Sending payload ("+s+")...");
  if (radio.write(s.c_str(), sizeof(s))) {
    Serial.println("successfull (response received).");
  } else {
    Serial.println("no response.");
  }
}

String input;
void loop() {
  input = Serial.readStringUntil('\n');
  if (input != "") {
    sendData(input);
  }
}