司机室话筒   Mike of driver’s cab

PA话筒应为电容(无噪声)声压型，其特点如下：
Pa mike shall be capacitance (noiseless) sound pressure type, its features are as follows:

话筒与系统其它部分兼容并带有各自的前置放大器。要求的频率响应为200Hz到10KHz，7dB。 前置放大器应完全符合UIC568标准对频率响应和畸变的要求。
Mike shall be compatible with other parts of the system and with separate pre-amplifier. Frequency response is required within 200hz to 10khz,  7db. Preamplifier shall completely comply with the requirement for frequency response and distortion in standard of uic568.

华译网北京翻译公司翻译过大量有关司机室话筒的文件资料。
Beijing Mandarin Chinese Translation Service Company has translated many technical documents in the field of Mike of driver’s cab.

客室应急对讲装置  Emergent intercommunicating device of passenger room
客室应急对讲装置集话筒、扬声器、紧急报警按钮为一体，话筒应为嵌入式电容（无噪声）声压型，其特点如下：话筒与系统其它部分兼容并带有各自的前置放大器。要求的频率响应为200Hz到10KHz，7dB。 前置放大器应完全符合UIC568标准对频率响应和畸变的要求。
Emergent intercommunicating device of passenger room shall incorporate mike, loudspeaker and emergent alarm button, the mike shall be built-in capacitance (noiseless) sound pressure type, its features are as follows: mike shall be compatible with other parts of the system and with separate pre-amplifier. Frequency response is required within 200hz to 10khz,  7db. Preamplifier shall completely comply with the requirement for frequency response and distortion in standard of uic568.

放大器  Amplifier
额定输出的频响范围： 100～12,000Hz；
Frequency response range of rated output: 100～12,000Hz；
额定输出时的偏差： ＋1/－2dB（均衡控制达到“平直”）
Deviation under rated output: ＋1/－2db (equilibrium control up to “flatness”)
于70Hz的频率响应： 每倍频程 -6Db
Frequency response below 70hz: -6db per octave
总谐波畸变(无压缩)： 5%，1000Hz，额定输出；
Total harmonic distortion (non-compression): 5%, 1000hz, rated output;
1%，1000Hz，50%额定输出
1%, 1000hz, 50% rated output;

在额定输入时，限制器电路输出电平误差不大于3dB，在全限制时谐波畸变不大于0.5%。放大器的输出符合标准UIC568关于频率特性和失真的要求。放大器设备(包括功率放大器)应能在输入或输出上承受不确定的短路或开路而不损坏，并满足IEC60571:1998的要求。
Under rated input, error of output level of limiter circuit shall be no more than 3db, under full limitation harmonic distortion shall be no more than 0.5%. Output of amplifier shall comply with the requirements of frequency feature and distortion in standard of uic568.
Input and output of amplifier devices (including power amplifiers) shall be capable of bearing uncertain short or open, no damage appears, and meet the requirements in iec60571:1998.
放大器的有效输出功率应不小于40W，并应能完全满足扬声器的输入要求。
Efficient output power of amplifier shall be no less than 40w, and completely meet the input requirements of loudspeaker.