Overview
he model 5105 is a compact dual-phase lock-in amplifier ideal for those signal recovery applications not demanding the performance offered by more sophisticated instruments in the SIGNAL RECOVERY range. It does not incorporate controls for manual operation but instead is operated entirely via an RS232 interface using simple ASCII character string commands. This approach allows the unit to be located closer to the signal source than is the case with PC card based instruments, thereby improving performance.
The instrument uses two switching type (squarewave) demodulators to measure the magnitude of the input signal in-phase (X) and in quadrature (Y) with the applied reference signal, and outputs both analog and digital representations of these values. The analog outputs are provided at front panel BNC connectors while the digital values, and in addition the resulting signal vector magnitude and phase angle, are available as responses to RS232 commands.
The signal channel includes high and low-pass filters which can be set to “bracket” the signal of interest thereby further improving the noise rejection, while the reference channel will operate from an external TTL or analog reference waveform.
Included with each instrument is a copy of 5105Acquire, a simple but versatile software package supporting up to ten instruments for Windows PC, giving access to all the instrument's controls and outputs. In addition, LabVIEW drivers are available for users wishing to use that environment to develop their own control software.
Supplied complete with a separate line power supply and 9-pin RS232 cable, the model 5105 is ready to use "out of the box". Its low cost and high performance allows phase sensitive signal recovery techniques to be used in many new applications.
Specifications
General
Dual-phase analog lock-in amplifier operating over a reference frequency range of 5 Hz to 20 kHz, but also available calibrated for use at one user=specified spot frequency in the range 20 kHz to 100 kHz
Measurement Modes The instrument can simultaneously measure these outputs: X In-phase Y Quadrature R Magnitude ø Phase Angle |
|
Harmonic | F only |
Signal Channel | |
Modes | Pseudo-differential |
Grounding | BNC shield can be grounded or floated via 1 kΩ to ground |
Full-scale Sensitivity | 10 µV to 1 V in a 1-3. 6-10 sequence (10 dB steps) |
Max. Dynamic Reserve | > 80 dB |
Impedance | 10 MΩ // 30pF |
Maximum Safe Input | 20 V pk-pk |
Voltage Noise | < 30 nV/√Hz @ 1 kHz |
C.M.R.R. | < 40 dB @ 1 kHz |
Frequency Response | 5 Hz to 100 kHz |
Gain Accuracy | ±2% typical for digital outputs; ± 6% typical for analog outputs |
Gain Stability | 200 ppm/ºC typical |
Signal Channel Filters | |
High-pass Signal Channel Filter -3 dB frequency |
1 Hz, 10 Hz, 100 Hz or 1 kHz |
Low-pass Signal Channel Filter -3 dB frequency |
50 Hz, 500 Hz, 5 kHz or 50 kHz |
Frequency Accuracy | ± 10% |
Reference Channel | |
Mode | TTL or Analog |
Frequency Range Analog Impedance |
5 Hz to 20 kHz 1 MΩ // 30 pF |
Phase Set Resolution | 0.1º increments |
Phase Set Accuracy | ± 1º |
Phase Noise | ≤ 0.015º rms @ 1 kHz, 100 ms, 12 dB TC ≤ 0.007º rms @ 10 kHz, 100 ms, 12 dB TC |
Phase Drift | , 0.05º/ºC |
Orthogonality | ± 1º |
Acquisition Time | 1 s + 2 cycles max |
Demodulator and Output Processing | |
Mode | Squarewave switching demodulator + HP/LP filters |
Zero stability/Dynamic Reserve
Mode | Dynamic Reserve (Filters Off) | Zero Stability |
High | 46 dB | 500 ppm/ºC |
DR | ||
Normal | 26 dB | 100 ppm/ºC |
High | 6 dB | 40 ppm/ºC |
Stability |
Output Filters Time Constants Analog and Digital Outputs Fast Mode Normal Mode Digital Outputs only |
300 µs, 1 ms, 3ms or 10 ms (316 µV to 1 V FS sensitivity) |
Accuracy | ±10% |
Slope | 6 dB/octave or 12 dB/octave |
Offsets | ±20% full-scale, X and/or Y |
Outputs | |
Main Analog (X and Y) Outputs Ampliltude Impedance |
±1 V FS |
Signal Monitor | 10 V pk-pk maximum |
Reference Output Waveform Impedance |
0 to 5 V rectangular wave |
Interface | |
Type |
RS232 via 9-pin D type plug, configured as a DTE device. Two ports are provided allowing up to sixteen model 5105 or compatible instruments to be controlled from a single computer port |
Parameters (fixed) | 4800 baud, no parity, 8 data bits and 1 stop bit |
Addressing |
Rear panel rotary switch assigns a unique address to each instrument |
Controls |
Sensitivity, High and Low- Pass Filter settings, Dynamic Reserve, Reference Phase, Time Constant and Slope can all be set and read via RS232 command |
Auto Functions | Auto-Phase and Auto-Phase |
Data Transfer Rate | 6-8 readings per second typical |
Outputs X and Y Magnitude Signal Phase Ref Frequency |
Max count = ±1200 (±1000=FS) Max count = 1200 (1000=FS) Max count=±1800, corresponding to ±180º Response in millihertz |
General | |
Software & RS232 Cable | 5105Acquire, a full applications package from IBM PC or 100% compatible computer and supporting up to ten instruments, is suppliled with each unit. This package allows access to all instrument controls and displays two selected instrument outputs.
In addition, a LabVIEW driver suitable fro version 4.01 and later of LabVIEW is available by download from our website at www.signalrecovery.com The instrument is also compatible with the full SIGNAL RECOVERY Acquire Lock-in Amplifier Applications software. A free demonstration version can be downloaded from the above website. 2 meter null-modem cable suitable for connecting the instrument to a 9-pin D-type RS232 plug on a PC computer is also included |
Power Requirements | +18 V DC unregulated @ 300 mA -18 V DC unregulated @ 80 mA A separate power supply (model PS0108) suitable for 110 V V 60 Hz or 230 V 50 Hz operation is supplied with each instrument |
Dimensions Width Depth Height |
8¼" (209 mm) 10½" (266 mm) 3½" (85 mm) |
Weight | 5 lb (2.3 kg) |