Theremin

Actually, I wasn't planing on making a theremin, I was exploring the arduino sound capability and kinda drift into it...
This is an easy Saturday project.

Whatch

You will need :
Arduino - I used the pro mini
Breadboard
220 ohm resistor
A speaker
an Infrared proximity sensor

The arduino sens the proximity of the hand and divide it to 15 notes according to the 4th and 5th octave ending with the 6th C to realize what note to play
Then according to where the output Hertz are at the moment it will decrease or increase to match that note.

int oct [15] = {262, 294, 330, 349, 392, 440, 494, 523, 587, 659, 698, 784, 880, 988, 1047};

int Play = oct [0];

void setup (){
    pinMode (5, OUTPUT);
    pinMode (A1, INPUT);
    Serial.begin (9600);
}

void loop (){
  int Hz = constrain (map (analogRead (A1), 100, 500,0, 14), 1, 14);
  Serial.println (Play);
  if (Play > oct [Hz]) {Play = Play - 6;}
  if (Play < oct [Hz]) {Play = Play+6;}
  tone (5,Play );
   // delay (100);
}