Abstract: A coaxial cable includes an inner conductor, an insulation covering the inner conductor, an outer conductor covering the insulation, and a sheath covering the outer conductor. The inner conductor is a compressed conductor including a central element wire and multiple peripheral element wires surrounding the central element wire. The inner conductor has a compressibility of 23.0% or more and 35.0% or less in percentage. The compressibility is calculated from a sectional area S1 and the sectional area S2 of the compressed conductor by Compressibility=[1?S2/S1]. The sectional area S1 is calculated from the outside diameter D of the central element wire and the total number n of the central and peripheral element wires by S1=n×?×0.25×D2. The outside diameter of the insulation is 1.25 mm or more and less than 1.75 mm.

Abstract: A liquid ejection head includes a nozzle for ejecting a droplet of a liquid, a pressure chamber connected to the nozzle, an actuator for changing a volume of the chamber according to a voltage signal, and a drive circuit generating the signal for ejecting n droplets, where n is an integer of 3 or more. The signal includes (n?1) ejection pulses, comprising a first pulse lowering the voltage signal to a first value to expand the chamber and then to a second value to contract the chamber, and a second pulse lowering the voltage signal to the first value and then to a third value higher than the second value. The pulses are input at intervals of 0.8? to 1.2?, where ? is a primary natural vibration period of the chamber filled with the liquid.