前置放大器

Most are matched pairs but this is actually not too critical in the testing setup which is as follows : CD : Sony S7000 + Theta TLC + Adcom GDA 600 + WE93F Pre-amp : ARC LS-7 Power Amp : 2 x Audion Sterling (in monoblock single EL34 mode) Speaker : KEF LS3/5a Each pair of tube is used on the input buffer of the Audion Sterling.

多数是被匹配的对但这实际上不是太重要的在是的测试的设定如下： CD：索尼S7000 +希腊字母的第八字TLC + Adcom GDA 600 + WE93F 前置放大器：弧LS-7 力量安培： 2 x 三极管英镑(在monoblock 唯一EL34 方式下)报告人： KEF LS3/5.a 各对管被使用在三极管英镑的输入缓冲区。

If you only have an old turntable and no amplifier, you will need to amplify the signal using a pre-amplifier before plugging it into the PC sound card.

如果你只有一个老唱盘，没有放大器，你需要使用前置放大器将信号放大，然后再将其与电脑声卡连接。

There are prepositive and main amplifier circuits in the detector, all-in-one design assures better stability and higher reliability of the instrument.

探测器内包含前置放大器与主放大器电路，一体化设计保证仪器有更好的稳定性和更高可靠性

So we designed a adaptive synchronizing controller based on hereinbefore hardware environment: first a small magnitude reference signal r is outputted to system through the signal card (to ensure that the vibrating system works in a linear state), and this signal is sent to the moving coil of vibrator through the power amplifier, so vibration is produced through electromagnetic induction. Secondly the vibration signal can feedback to the data acquiring card in the servo system through the acceleration sensor on the Vibroseis reactor M〓 and the base-plate M〓, then the computer can get the current vibrating state y〓 of the coil of vibrator according to the feedback information from the data acquiring card, and give a real time comparing between the current state y〓 and the reference output y〓 of the set-in reference model with current reference input being r , then regulates the correlative controlling parameters according to the error e〓=y〓-y〓 till y〓→y〓, finally normal signal sweeping begins with a certain phase fixed. Meanwhile a synchronization signal for seismic signal record is sent to seismograph from synchronization signal outputting component in the Vibroseis system to perform the controlling process of synchronization of sweeping phases.

为此，我们基于以上的硬件环境设计了一个自适应同步控制器：首先通过信号发生卡对系统输出小幅度的参考信号r(从而保证振动系统工作处于线性状态)，信号通过前置放大器、功率放大器等送到激震器动圈，并通过电磁感应产生振动，振动信号通过可控震源激震器反应块M〓和基板M〓上的加速度传感器反馈给伺服系统中的数据采集卡，工控计算机根据采集卡的反馈信息，获取当前激震器动圈的振动状态y〓，并实时地将该状态与内置的参考模型在当前参考输入r下的参考输出y〓进行辨识，再将两者输出误差e〓＝y〓-y〓对系统的有关控制参数进行调整，直至y〓→y〓，最后在经过某一固定的相位后，开始信号的正常扫描过程，与此同时，由可控震源系统的同步信号输出部件向地震仪送出一地震信号记录同步信号，进而完成扫描相位同步控制过程。

There are three parts included. The first part is the prepositive-amplifier, it gets broadband high gain and flat frequency response. The second part is the U band quadrupler, which composed of two doublers using a PHEMT chip HMMC-5040, a Schottky diode of DMK-2790, a HMMC-5040 amplifier, and a fin-line transitional stage. Maximum output power higher than 60mW is obtained in V band. The third part is a 2nd harmonic gunn oscillator injection locked by the Fundamental Wave,which get about 2GHz locked bandwidth in W band.

电路主要由三部分组成，第一部分为采用HMMC-5618设计的前置放大器，实现了宽带高增益和平坦的频率响应；第二部分为设计的主体，由HMMC-5040设计的二倍频器、DMK-2790设计的二倍频器、HMMC-5040设计的放大器及鳍线过渡段组成的U波段四倍频器，在U波段实现了最高60mW以上的输出功率；第三部分为基波注入锁定谐波Gunn振荡器，在W波段实现了近2GHz锁定带宽。

The use of battery power is good both for audio preamps and amplifiers.

对音频前置放大器和放大器来说，使用电池供电都是合适的。

This external unit interfaces through a USB port and features a 1024 channel MCA with internal preamplifier, computer controlled amplifier, high voltage (0-2048V), upper and lower level discriminators and multichannel scaling for half-life and decay studies.

外置单元通过 USB 接口接电脑，1024道 MCA 和前置放大器，电脑控制放大器，高压（0-2048V ），上平和下平鉴别器和多道测量可做半衰和衰变的学习研究。

Based on the structure of classical instrumental amplifier,a preamplifier for the measurement of EEG signals is improved and designed.

基于经典的仪表放大器基本框架，改进和设计了一种可用于心电信号采集的前置放大器。

For over 40 years, Dragan has published articles with different original constructions of power amplifiers, low noise preamplifantennas for HF, VHF, UHF and SHF bands.

四十年来，Dragan 出版了多版本的 HF，VHF，和 SHF 频段的功率放大器，低噪音前置放大器的著作。1964 年他获得业余无线电许可证。

For over 40 years, Dragan has published articles with different original constructions of power amplifiers, low noise preamplifiers, antennas for HF, VHF, UHF and SHF bands.

四十年来，Dragan 出版了多版本的 HF，VHF，和 SHF 频段的功率放大器，低噪音前置放大器的著作。1964 年他获得业余无线电许可证。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。