This may sound a little silly but i have noticed that while flying with radar contact, sometimes ATC will say something like "QNH 1010" usually when i am desending towards an airport. I thought it meant altimeter but i fly the PMDG 747 and i have not seen a button for adjusting QNH (whatever that means) anywhere.What exactly is QNH? And can any PMDG flyers let me know where this can be adjusted on the panel?Also, i find that sometimes, when i level off after an instruction to desend, ATC keep telling me that i am not at the right altitude. But i am and i check to make sure that the altimeter is correct and it is. But ATC keeps reporting that i am not at the right altitude. Why is that?Anthony

Anthony,Understanding QNH, altitudes and Flight Levels is fundamental to flying correctly with RC. All the information about this is available in the extensive manual. Take some time to read about it and I'm sure the fog will lift. :-)The altimeter pressure is adjustable via a small knob on that instrument. Many RC users fly the PMDG747 so may be able to point you to it.If you have any specific questions having read the sections come back and we'll help.Cheers,