i bough a cheap ph sensor module to mess around with. i found some sketches online that talk about this module but im not getting the same result from the analog voltage pins as they are. this is the module i bought it seemed promising but i cannot turn the trim pot down low enough to drop the voltage down to 2.5 volts like instructed in the tutorial but insted 2.6 volts but even then the reading is completely wrong. maybe someone here has used this module or know whats going on. here is a link to the tutorial i was following and i will pst the offset calibration code below also i am using an arduino mega and powering the module at 5.0 volts exactly. thanks
void setup() {
// initialize serial communication at 9600 bits per second:
Serial.begin(9600);
}
// the loop routine runs over and over showing the voltage on A0
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);
delay(300);
}