An exemplary burning system for a liquid crystal display includes an optic-electric transformer, a comparator circuit, and a micro-controller unit. A microphone is installed in the mounting hole via the first and second fixtures. The check valve arrangement is defined by a valve element movable into and out of engagement with a valve seat wherein one of the valve element and the valve seat has a first sealing structure engageable with a second sealing structure on the other of the valve element and the valve seat. Carrier phase of the signal is estimated based upon the overhead field.