A percussion drill bit is provided that has at least two different pluralities of inserts extending from the bit head to better match the conditions seen on the bit head during drilling. In a pressure amplifier of the above-described type, the outlet duct opens into the circumferential wall or extends through a connection plug which is screwed into the end face on the high pressure side and closes off an assembly duct which receives the outlet valve. The reduced gray-scale voltage taps reduces the circuit scale and the test procedures for the drive circuit. When the operation input receiving unit detects a tracing operation in which the touch moves by a predetermined distance while touching the operation input receiving unit, the tracing operation starting from the additional information access entrance, the state of display is forced to transit. To this end, the compensatory permanent magnets are arranged in the vicinity of the contact bridge and polarized in the opposite direction of the blow magnets. The television is operable to display content of the multimedia data stream on the display promptly upon receipt of a user request to power up the television.