美国斯坦福SRS 射频锁相放大器SR844
25kHz—200MHz频率范围, 100s -30ks时间常数；6，12，18，24dB/倍频程衰减,
内部或外部参考源；自动量程；存储和调用9个仪器设备, 标准GPIB，RS—232接口
The SR844 is the widest bandwidth lock-in amplifier available. It provides
uncompromised performance with a frequency range of 25 kHz to 200 MHz and up to 80 dB
of drift-free dynamic reserve. It includes the many features, ease of operation, and
programmability that you've come to expect from SRS DSP lock-in amplifiers.
· 25 kHz to 200 MHz frequency range
· 80 dB dynamic reserve
· Time constants from 100 μs to 30 ks (6, 12, 18 or 24 dB/oct rolloff)
· "No Time Constant" mode (10 μs to 20 μs update rate)
· Auto-gain, -phase, -reserve and -offset
· Two 16-bit DACs and ADCs
· Internal or external reference
· GPIB and RS-232 interfaces
