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一、Békésy自动描记听力计自动描记听力计是以它的发明者Békésy的名字命名的。这种仪器利用一个频率范围从100—10000Hz的拍频振荡器发出脉冲的或连续的纯音讯号,脉冲音讯号持续200ms,中断200ms(亦有“开”260ms,“关”260ms,上升下降时间40ms)。讯号频率的转换用一个电动马达来控制,它可以在100—10000Hz(或8000Hz)的频率范围内以从低到高的形式来增加讯号的频率。即扫频方式。电动马达也可以被阻断而由检查者来操纵频率的转换装置,以便对听力计频率范围内的任何单一频率进行连续测试,即固定频率的方式。纯音讯号的强度由受试者操纵的衰减器马达手控开关来控制。衰减器马达使测试讯号的强度均匀而平稳的增加,当病人听到声音的时候,他按压手控开关,使衰减器马达倒转而引起讯号的强度减低。当病人听不到声音的时候,将手控开关放松,则衰减器马达使讯号的强度重新
A, Békésy automatic description audiometer Automatic description audiometer is named after its inventor Békésy. This instrument uses a beat frequency of 100-10000Hz beat frequency or continuous pure tone signal, the pulse tone signal lasts 200ms, interrupt 200ms (also have “on” 260ms, “off” 260ms, rise and fall time 40ms ). The conversion of the signal frequency is controlled by an electric motor which increases the frequency of the signal in a low to high frequency range of 100-10000 Hz (or 8000 Hz). That sweep the way. The electric motor can also be switched off and the examiner to manipulate the frequency conversion means to continuously test any single frequency in the audible frequency range, ie a fixed frequency. The intensity of the pure tone signal is controlled by the subject manipulated attenuator motor manual switch. Attenuator motor to test the signal strength of the uniform and steady increase, when the patient heard the sound, he pressed the manual switch, so that the attenuator motor reverse caused by the signal strength decreased. When the patient can not hear the sound, the manual switch to relax, then the attenuator motor to signal strength again