   Serial.print("C ");
   Serial.print(h);
   Serial.println("%");
-  
-  oregon.send(t, h, readVcc()>1200?1:0); // send the sensor readings
+  Serial.print(Vcc);
+  Serial.println("mV");
+
+  oregon.send(t, h, Vcc > 1200 * 2 ? 1 : 0); // send the sensor readings
 
   // Wait for one minute
-  for( index = 0 ; index < 60/8 ; index++ )
+  for ( index = 0 ; index < 60 / 8 ; index++ )
   {
     // Sleep for 8 s with ADC module and BOD module off
     LowPower.powerDown(SLEEP_8S, ADC_OFF, BOD_OFF);

long readVcc() {
  // Read 1.1V reference against AVcc
  // set the reference to Vcc and the measurement to the internal 1.1V reference
  #if defined(__AVR_ATmega32U4__) || defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__)
    ADMUX = _BV(REFS0) | _BV(MUX4) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1);
  #elif defined (__AVR_ATtiny24__) || defined(__AVR_ATtiny44__) || defined(__AVR_ATtiny84__)
    ADMUX = _BV(MUX5) | _BV(MUX0);
  #elif defined (__AVR_ATtiny25__) || defined(__AVR_ATtiny45__) || defined(__AVR_ATtiny85__)
    ADMUX = _BV(MUX3) | _BV(MUX2);
  #else
    ADMUX = _BV(REFS0) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1);
  #endif  

  delay(2); // Wait for Vref to settle
  ADCSRA |= _BV(ADSC); // Start conversion
  while (bit_is_set(ADCSRA,ADSC)); // measuring

  uint8_t low  = ADCL; // must read ADCL first - it then locks ADCH  
  uint8_t high = ADCH; // unlocks both

  long result = (high<<8) | low;

  result = 1125300L / result; // Calculate Vcc (in mV); 1125300 = 1.1*1023*1000
  return result; // Vcc in millivolts

/*
   https://github.com/r2d2/ard-stuff
   Temperature and humidity sensor / Oregon sender
   Uses a DHT series temperature and humidity sensor and an RF transmitter
   Requires the following Arduino libraries to be installed in the libraries directory:
   - DHT from https://github.com/markruys/arduino-DHT
   - LowPower lib from https://github.com/rocketscream/Low-Power
   - oregon lib from https://github.com/r2d2/ard-stuff/ard-libraries
*/

#include <DHT.h>
#include <LowPower.h>
