how to reduce the electrical noise

paimpozhil:

mixania:
I think a pull–up resistor between a pin and VCC would help.

Which pin and VCC ? sorry im very new to arduino land.

For example: If you are using a wire (you would actually be using at least two in this case) to communicate with another Arduino. And you would want to reduce the noise, consider connecting a part of the wire to the vcc through a pull-up resistor. Connect the end of the wire to the final destination.