Arduino theremin problem.

SI followed the procedure on this website

However nothing happens when it's plugged into power. This is my first project so sorry if it is an easy question.

I copied and pasted the code an uploaded into the arduino uno.

Here is the image

Ok, you need to take a few steps back. I am absolutely sure that something happened. Did the LED come on? Did your computer make the USB-connect noise? It is literally impossible that nothing happened.

Does the Arduino work with absolutely nothing plugged in? Can you upload the Blink sketch and see it blinking?

Those F***ing diagrams are very difficult to read. You may need to check your connections five times.

The arduino lights flashed when it came on when i connected the usb however the led did nothing and did not blink.

Ched: I copied and pasted the code an uploaded into the arduino uno.

How about copy and pasting it here so we might have a hope in hell of seeing what you did wrong?

DON'T copy it again from where you got it. Copy it from the IDE where you compiled it and uploaded it. We need to see what actually got loaded to the board, not what you think got loaded.

// What digital pin is the speaker on?
// (The other speaker wire should connect to Gnd.)
int SPEAKER = 8;

// which analog pin is the light sensor on?

// Typical photocell values for daytime
// with window and 1k resistor:
// min 15, max 100.
#define MIN_SIGNAL 15 /* 100 /
#define MAX_SIGNAL 100 /
1024 */

// What frequencies should we allow (in Hertz)?
// Typical human hearing is 20 Hz to 20,000 Hz,
// but our piezo buzzers can’t reproduce such a wide range.
// 100 to 10k or so is usually okay.
#define MIN_FREQ 100
#define MAX_FREQ 8000

// How many samples should we read from the sensor each time?
// The sensor is noisy, so there will be a lot of spurious readings.
#define NUM_SAMPLES 15

// To monitor the output from the sensor (so you can calibrate MAX_SIGNAL
// and MIN_SIGNAL), uncomment SERIAL_DEBUG:
//#define SERIAL_DEBUG 1

void setup()


void loop()
// Set the frequency according to the light value read off analog pin 0.

// Average 5 reads
int lightsensor = 0;
for (int i=1; i < NUM_SAMPLES; ++i)
lightsensor += analogRead(LIGHTSENSOR);
lightsensor /= NUM_SAMPLES;

unsigned int freq = map(lightsensor,

tone(SPEAKER, freq);

Serial.print("Read “);
Serial.print(” → ");
The theremin code

Turns on an LED on for one second, then off for one second, repeatedly.

Most Arduinos have an on-board LED you can control. On the Uno and
Leonardo, it is attached to digital pin 13. If you’re unsure what
pin the on-board LED is connected to on your Arduino model, check
the documentation at

This example code is in the public domain.

modified 8 May 2014
by Scott Fitzgerald

// the setup function runs once when you press reset or power the board
void setup() {
// initialize digital pin 13 as an output.
pinMode(13, OUTPUT);

// the loop function runs over and over again forever
void loop() {
digitalWrite(13, HIGH); // turn the LED on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(13, LOW); // turn the LED off by making the voltage LOW
delay(1000); // wait for a second

LED blink code

Speaker is pin8, your and the original diagram are using pin 10.

Move wire from 10 to 8.
or change
int SPEAKER = 8;
int SPEAKER = 10;

Hope it fixes the problem… Tom… :slight_smile:

Can you please post a copy of your sketch, using code tags?
They are made with the </> icon in the reply Menu.
See section 7,148850.0.html

Tom… :slight_smile: