I plugged in my 750 this evening and proceeded to calibrate it. Well when I push the cal button it turns the scale off. Just like when you use the on/off button. When I push the cal button the screen says off and it shuts off. I haven't used it in a few months but it was working fine last time. Its plugged into the same outlet that it normally is. Any ideas? Appreciate it. Also, I've had it longer than a year. The manual says 1 year warranty. Any chance RCBS sends me a new one if I can't get it working? I don't have any experience with their customer service.