Thanks outsider for the reply.
I hooked things up as per
and used the following code snippet to rule out my code as being an issue.
/*
ReadAnalogVoltage
Reads an analog input on pin 0, converts it to voltage, and prints the result to the Serial Monitor.
Graphical representation is available using Serial Plotter (Tools > Serial Plotter menu).
Attach the center pin of a potentiometer to pin A0, and the outside pins to +5V and ground.
This example code is in the public domain.
http://www.arduino.cc/en/Tutorial/ReadAnalogVoltage
*/
// the setup routine runs once when you press reset:
void setup() {
// initialize serial communication at 9600 bits per second:
Serial.begin(9600);
}
// the loop routine runs over and over again forever:
void loop() {
// read the input on analog pin 0:
int sensorValue = analogRead(A0);
// Convert the analog reading (which goes from 0 - 1023) to a voltage (0 - 5V):
float voltage = sensorValue * (5.0 / 1023.0);
// print out the value you read:
Serial.println(voltage);
}
I see values in the serial monitor of 1.6 irrespective if the PNP laser sensor receiver goes from high to low when a laser is shone at it yet if I use a multi meter and measure DC volts between GND and SIG on the volateg divider there is a clear change which is what I dont get, why doesnt the Arduino see this.
When I unplug A0 from the Arduino this drops instantly to 1.2.
Still pretty stuck here.
Is it possible to bypass the voltage divider and use the 2.2k ohm resistor.
Apologies, still an electronics novice and appreciate everyones help here.