SR830 SR810 SR850 SR865 SR530 SR510 SR540 SR560 SR124 LDC500 SR470 SR570 SR445A SR554 SR550 SR552 SR555 SR556 SIM910 SIM911 DG645 SIM918 DG535 DB64 PTC10 CTC100 SIM900 PS300 SR400 SR430 BOXCAR CS580 SG380 CG635 DS345 DS360 DS335 DS340 SR760&SR770 SR785 SR780 SR1 SR630 SR715和SR720 SR600 NL100 IGC100 QCM200 MPA100 RGA100/RGA200/RGA300 UGA/ULT QMS PPR SC10 PRS10 FS725 SR620 SR625 FS700 FS730/SRS735信号分配放大器

· 1 mHz to 2 MHz frequency range (operates to 2.5 MHz) · Dual reference mode · Low-noise current and voltage inputs · Touchscreen data display - large numeric answers, chart recordings, & FFT displays · 10 MHz timebase input and output · GPIB, RS-232, Ethernet and USB · HDMI video output · SR865 $7950 (U.S. list) SR865 2 MHz Lock-In Amplifier The SR865 2 MHz Lock-In Amplifier delivers the performance needed in the most demanding synchronous detection applications. This FPGA based instrument offers a wide frequency range (0.001 Hz to 2 MHz), high dynamic reserve (>120 dB), excellent stability (<5 ppm/°c), and high phase resolution (0.1 µdeg.). building on the industry standard sr830, this next-generation lock-in amplifier has several analog enhancements and many new features not found in other instruments. a built-in touchscreen display shows the instantaneous results of your measurement, as well as its complete time history. the instrument is also easy to use — all instrument function have dedicated buttons and knobs. signal inputs the sr865 has state-of-the-art voltage and current inputs. the voltage input is a single-ended/differential fet preamplifier that has less than 2.5 nv/√hz input noise at 1 khz, and less than 10 nv/√hz at 10 hz. it has 10 mΩ input impedance and can be ac or dc coupled. the current input offers a choice of 106 or 108 v/a gain, and has up to 400 khz of bandwidth and as little as 13 fa/√hz input current noise. the sr865 can operate in either ground or float mode. there are several srs preamplifiers including the sr550 (fet input), sr552 (bjt input), sr554 (transformer input), sr555 (120 khz current amp) and sr556 (low noise current amp) which can all be powered directly from the sr865’s rear-panel preamp power port. each preamp is optimized for different experimental conditions, and when used with the sr865, they can often signific

Input Range On the front panel of the SR865, an input range button replaces the sensitivity and dynamic reserve buttons found on older digital lock-in amplifiers. You simply choose the lowest range that doesn’t cause an overload. Small LED bar graphs indicate the percentage of full scale for each of the five range settings. Output Time Constants Output time constants from 1 µs to 30 ks with 6, 12, 18 or 24 dB/oct rolloff let you optimize the signal-to-noise ratio of your measurements. Synchronous filters are available below 4 kHz which notch out multiples of the reference frequency and can be extremely useful for low frequency measurements. Unlike previous models, there is no output resolution trade-off for using the synchronous filters. Advanced Filters The SR865 also provides advanced filtering in place of the traditional 6dB/oct RC filters. These filters can provide digital filtering that has no analog filter counterpart. At time constants of 3 s and faster, these advanced filters are pass the same amount of noise as the corresponding RC filter but have much faster settling times. If the input signal is changing rapidly, or if there is significant noise away from the reference frequency, then the advanced filters often provide better signal to noise with faster output response. For time constants of 10 s and longer, the advanced filters are implemented to align the stop bａnd with the corresponding classical RC analog filter. These filters settle to their final values nearly twice as fast as the RC filter. Reference Channel The reference source of the SR865 can set to Internal, External, Dual or Chop modes. In Internal mode, the reference frequency is set from 0.001 Hz to 2 MHz. In External mode, an external sine wave or square wave determines the reference frequency, and there is a choice of 50 Ω or 1 MΩ input termination. In either mode, the SR865 can also detect harmonics of the reference frequency. Any harmonic, from the fundamental up to the 99th harmonic, can be detected. In Dual F Reference mode (Dual), the SR865 detects at the difference between the internally set reference frequency and an external reference frequency. In this mode, the SR865 provides direct recovery of a double-modulated signal. In Chopper Reference mode (Chop), the SR865 uses PID control to synchronize a remote SR540 Optical Chopper to the high-stability internal reference of the lock-in. The excessive frequency drift of the chopper is virtually eliminated. External 10MHz Timebase Input and Output The SR865 has a reference 10 MHz timebase input and output on the rear panel. This allows the SR865 to be locked to an external reference (like the FS725 10 MHz Rubidium Frequency Standard), or to synchronize several SR865s and/ or other test equipment with a 10 MHz reference input. Source Output A spectrally clean source (-80 dB) with DC offset is a standard feature of the SR865. The sine output source can be operated in standard single-end mode or differentially — new to lockins. In differential mode you can have signals as small as 1 nV or as large as 2 volts with up to 5 volts of DC offset. Frequency can be set with up to 6 digits of resolution. Sync Output / BlazeX In addition to the sine source, there is a logic level sync signal available on the rear panel. This output also serves as the BlazeX output which is a low latency output (<2 µs delay) ideal in control loop applications. front-panel operation and touchscreen data display for the seasoned lock-in user, the sr865 front panel will seem quite familiar. all instrument controls have dedicated frontpanel buttons and knobs — there is no obscure menu tree to navigate. so changing a time constant or adjusting the source amplitude is trivial. in addition, there is a colorful 640 × 480 touchscreen data display. four controllable data channels display and graph x, y, r, Θ, aux in 1 to 4, aux out 1 to 2, x noise, y noise, sine out amplitude, sine out dc level, reference phase, or fref. you can also scan and display the internal reference frequency, the sine out amplitude and offset, or the aux 1 and 2 outputs. all data sources are continually stored at all chart display time scales (17 scales from 0.5 seconds per division to 2 days per division) and available at any time to the user. there are several ways to view your data. there are large numbers that can easily be read from across the lab, chart recordings for a complete time history of your data, and fft displays of your signal input and the signal output. for situations where a dark lab is required, the touchscreen display and all front-panel leds can be turned off with the push of a button. communication the sr865 comes standard with gpib (ieee488.2), rs-232, usb device, and ethernet interfaces. all instrument functions can be queried and controlled using any of the interfaces.