How to do comparator

Hai there guys,
I am having problem again. Im doing comparator circuit. My problem is there is no output at my output pin although my reference pin is higher than the negative pin. I am using LM339 comparator. Can anyone help me with this?

Thank you

Please Provide Complete circuit Diagramme

Please provide the circuit you have made.

LM 339 series comparators are with open collector o/p, do not expect a voltage unless it properly biased from the +V supply
:bye

i m using a variable resistor to control the voltage to my V+ input. I am using ldr for my V-.