A method of managing memory in which a low-level mechanism is executed to signal, in a sequence of instructions generated at a higher level, that at least a portion of a contiguous area of memory is permitted to be overwritten. In a bypass circuit which bypasses the transmission final stage amplifier 6, a phase rotation compensating circuit, comprised of a variable capacitance capacitor 9 and a coil 10, and whose cutoff frequency can be adjustable by an adjustment voltage, is inserted in the middle of the bypass route. When recording voice with the electronic camera, shutter sound effects are not output with the recorded voice. An inter-signal condition determining unit compares a relationship between the peak of a main signal and the peak of sub-signals to a first condition, and excludes, from combining diversity, baseband signals corresponding to the sub-signals if the relationship does not satisfy the first condition. The recovered first gas is recirculated through the vacuum chamber, and the recovered second gas is recirculated through at least the pump.