The SR556 is a current preamplifier produced to work with SRS lock amplifiers. It is a noise-less, high-bandwidth, fixed-gain current or trans-impedance amplifier that works close to the experimental detector which allows the users to reduce input cable length and its equivalent input capacity. Noise and pickup are reduced by this device prior to their signal-to-ratio permanently degraded which then reduces time in noise-limited experiments.是一个电流产生sr556与SRS定放大器工作前置放大器。是一个无噪声带宽固定增益电流或抗放大器接实探测器允用户减少入电缆的度和它的等效入电容。噪声和干扰低了本置其信号之前比永久化从低了噪声制实时。