that's not what I meant, I meant that RAMPS 1.4 doesn't read from a thermocouple !! ... but I searched for it and found that it needs an extra module "thermocouple amplifier".
the most famous are AD595 op-amp circuit and MAX xxx something !!
I will build my own amplifier and connect it between my thermocouple and RAMPS 1.4
I found solutions there:
solution
reference RepRap Wiki