   // Configure the humidity sensor
   myHumidity.begin();
 
-  // Start EC sensor
-  FreqCount.begin(1000);
-
+  // Set output pins
+  pinMode(S1_EN, OUTPUT);
+  digitalWrite(S1_EN, HIGH);
+  pinMode(S2_EN, OUTPUT);
+  digitalWrite(S2_EN, HIGH);
+  pinMode(S3_EN, OUTPUT);
+  digitalWrite(S3_EN, HIGH);
+
+  pinMode(MULT_A, OUTPUT);
+  digitalWrite(MULT_A, HIGH);
+  pinMode(MULT_B, OUTPUT);
+  digitalWrite(MULT_B, HIGH);
+  pinMode(MULT_C, OUTPUT);
+  digitalWrite(MULT_C, LOW);
+  
   // Set key pin to low
   pinMode(FONA_KEY, OUTPUT);
   digitalWrite(FONA_KEY, LOW);

const byte FONA_RST = 12;
const byte FONA_EN_BAT = 13;

// Analog I/O pins
const byte LIGHT = A5; // Not currently used
const byte REFERENCE_3V3 = A3; // Not currently used
const byte WDIR = A0; // Not currently used
const byte PH_PIN = A4;
const byte ORP_PIN = A3;
const byte WTEMP_PIN = A15;
// Conductivity sensor (EC) uses pin 47 and disables pins 9, 10, 44, 45, 46.

// Offset values

  pressure = myPressure.readPressure();

  // Calc light level
  //light_lvl = get_light_level();

  // Calc EC
  delay(500);
  digitalWrite(S1_EN, LOW);
  FreqCount.begin(1000);
  while ( !FreqCount.available());
  ec = FreqCount.read();
  FreqCount.end();
  // TODO: calibrate value
  digitalWrite(S1_EN, HIGH);

  // Calc orp
  delay(500);
  digitalWrite(S2_EN, LOW);
  delay(1000);
  orp = (30.0 * SYSTEM_VOLTAGE * 1000.0) - (75.0 * analogRead(ORP_PIN) *
      SYSTEM_VOLTAGE * 1000 / 1024.0);
  orp = (orp / 75.0) - ORP_OFFSET;
  digitalWrite(S2_EN, HIGH);

  // Calc pH
  delay(500);
  digitalWrite(S3_EN, LOW);
  delay(1000);
  ph = analogRead(PH_PIN) * 5.0 / 1024;
  ph = 3.5 * ph + PH_OFFSET;
  digitalWrite(S3_EN, HIGH);

  // Calc water temperature
  wtemp = get_water_temperature();
