     Serial.print("\tangle: ");
     Serial.println(angle);
   
-    delay(TURN_AROUND_DELAY);
+    delay(random(1500, 3000));
   
-    digitalWrite(13, HIGH);   // turn the LED on (HIGH is the voltage level)
+    digitalWrite(LED_DIAG, HIGH);   // turn the LED on (HIGH is the voltage level)
     range = RIGHT_LIMIT - angle;
     skew = random(random(range));
     limit = RIGHT_LIMIT - skew;

#include <Math.h>
#include <Servo.h>

//
// CONSTANTS
//

// multiply by degrees to get radians
//
const double RADIANS_PER_DEGREE = 0.0174532925;

const int LEFT_LIMIT = 60;
const int RIGHT_LIMIT = 180;

// milliseconds to wait between servo movement: when servo is gently oscillating
const int GENTLE_DELAY = 45;

// milliseconds to wait between servo movement: when servo is shaking back & forth
const int SHAKE_DELAY = 10;

  Serial.println(behaviorMode);

  switch (behaviorMode) {

    case 0:
      currAngle = shakeServo(currAngle, random(2, 4));
      break;

    default:
      currAngle = oscillateGently(currAngle, random(3, 6));
      break;

  }

  // wait random seconds until next loop
