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7230 General Purpose DSP Lock-in Amplifier

7230 Lock-in Amplifier
Model 7230

The model 7230 is a new concept in general-purpose DSP lock-in amplifiers. This instrument is our next generation offering based from the 7225 lock-in amplifier. It offers the excellent signal recovery performance that users expect from our instruments at competitive price. The 7230 offers a virtual front panel via a web browser which gives it a low profile for integrating into larger system configurations.  This has been achieved by easy-to-use control panels that can be operated from any computer via your favorite browser. The 7230 offers the most versatility in any experiments configuration.

It is normally configured for operation over a frequency range extending from 1 mHz to 120 kHz. However, for a small extra charge it can also be delivered, or upgraded via a firmware update pack, to allow operation at frequencies of up to 250 kHz.

You can use any web compatible device to operate the model 7230, ranging from a simple netbook to the most powerful development machine, from an Android smartphone to the latest iPad. No special software is needed, since the panels work directly through the device’s browser. All that is necessary is that the computer and instrument be connected to the same Ethernet network.

The instrument is also much more compact than traditional designs, making it easier to accommodate in crowded laboratories, and as it does not include any cooling fans it is completely silent, which is especially useful for acoustic research.

In common with other models in our range the 7230 offers much more than just dual phase lock-in detection at the reference frequency of an applied signal. It includes features unique to SIGNAL RECOVERY instruments such as dual reference and dual harmonic detection, which allow signals at two different frequencies to be measured simultaneously, and tandem demodulation. It also includes virtual reference mode, allowing reference-free measurement of suitable signals.

Fast Data Processing
The main ADC sampling rate and the rate at which the analog signal outputs are updated is 1 MSa/s, giving excellent performance when used at short output filter time constant settings, such as in scanned probe measurements. The maximum rate at which data can be stored to the internal curve buffer is 1 μs per point, allowing direct capture of instrument outputs when using these short time constants. The buffer length of 100,000 sets of points gives a recording time of 100 ms at the fastest sampling rate.

Remote Control
The built-in web control pages allow full operation via the Ethernet interface, which with the USB and RS232 connections, can also be used to operate the instrument from our comprehensive software package, Acquire, from our ActiveX control and toolkit(SRInstComms), or using the free LabVIEW driver.

See what you’ve been missing...
In summary, the Model 7230 offers a very cost-effective solution to users who need a lock-in amplifier suitable for straightforward applications but with the versatility to also be used in complex experiments.

  • Documents +

  • Specifications +

    Signal Channel
    Voltage Input
    Modes A only, -B only or Differential (A-B)
    Frequency Response 1 mHz < F < 120 or 250 kHz*
    Full-scale Sensitivity 10 nV to 1 V in a 1-2-5 sequence (e.g. 10 nV, 20 nV, 50 nV, 100 nV, etc.)
    Impedance - FET input 10 MΩ // 25 pF, AC or DC coupled
    Impedance - Bipolar input 10 kΩ // 25 pF, input must be DC coupled
    Max safe input ±12.0 V
    Voltage Noise - FET input 5 nV/√Hz @ 1 kHz
    Voltage Noise - Bipolar input 2 nV/√Hz @ 1 kHz
    C.M.R.R. > 100 dB @ 1 kHz degrading by no more than 6 dB/octave with increasing frequency
    Gain Accuracy ±0.5% typ, ±1.0% max
    Distortion -90 dB THD (60 dB AC gain, 1 kHz)
    Current Input
    Mode Low Noise (10E8 V/A) or Wide Bandwidth (10E6 V/A)
    Full-scale Sensitivity
    Low Noise 10 fA to 10 nA in a 1-2-5 sequence
    Wide Bandwidth 10 fA to 1 µA in a 1-2-5 sequence
    Frequency Response (-3 dB):
    Low Noise 1 mHz < F < 500 Hz minimum
    Wide Bandwidth 1 mHz < F < 50 kHz minimum
    Low Noise < 2.5 kΩ @ 100 Hz
    Wide Bandwidth < 250 Ω @ 1 kHz
    Low Noise 13 fA/√Hz @ 500 Hz
    Wide Bandwidth 130 fA/√Hz @ 1 kHz
    Gain Accuracy ±2.0% typ, midband
    Either Input Mode
    Line Filter Filter can be set to attenuate 50/60 Hz, 100/120 Hz, or both frequency bands
    Max. Dynamic Reserve > 100 dB
    Grounding BNC shield can be grounded or floated via 1 kΩ to ground
    Signal Molnitor Amplitude ±1 V FS. This is the signal after preamplification and filtering, but before transmission over the optical link
    Output Impedance 1 kΩ
    Reference Channel
    Reference Input
    TTL input setting
    Freq. Range 1 mHz to 120 or 250 kHz*
    Analog input setting
    Impedance 1 MΩ // 30 pF
    Sinusoidal Level 1.0 V rms*
    Frequency Range 0.5 Hz to 250 kHz*
    Squarewave Input Level 250 mV rms
    Frequency Range 2 Hz to 120 or 250 kHz*
    Reference Channel
    Phase Set Resolution 0.001° increments
    Phase Noise at 100 ms TC, 12 dB/octave slope:
    Internal Reference < 0.0001° rms
    External Reference < 0.01° rms @ 1 kHz
    Orthogonality 90° ± 0.0001°
    Acquisition Time
    Internal Reference instantaneous acquisition
    External Reference 2 cycles + 1 s
    Reference Frequency Meter Resolution 4 ppm or 1 mHz, whichever is the greater
    Demodulator and Output Processing
    Output Filters
    Time Constant 10 µs to 100 ks in a 1-2-5 sequence
    Slope (roll-off):
    TC < 5 ms 6 or 12 dB/octave
    TC > 5 ms 6, 12, 18 or 24 dB/octave
    Synchronous Filter Available for F < 20 Hz
    Offset Auto and Manual on X and/or Y: ±300% full-scale
    Phase Measurement Resolution < 0.01º
    Reference Monitor Rear panel TRIG OUT connector can be configured to generate TTL signal at current reference frequency, internal or external
    Oscillator - General
    Range 1 mHz to 120 or 250 kHz*
    Setting Resolution 1 mHz
    Absolute Accuracy ± 50 ppm
    Range 1 µV to 5 V
    Max. Setting Resolution 1 µV
    Output impedance 50 Ω
    Frequency Sweep
    Output Range 1 mHz to 120 or 250 kHz*
    Law Linear or Logarithmic
    Step Rate 1 kHz maximum (1 ms/step)
    Amplitude Sweep
    Output Range 0.000 to 1.000 V rms
    Law Linear
    Step Rate 20 Hz maximum (50 ms/step)
    Oscillator Output
    Accuracy ±0.2% typ
    Stability 50 ppm/ºC
    Distortion (THD) -80 dB @ 1 kHz and 100 mV rms
    Data Storage Buffer
    Size 100,000 data points
    Max. Storage Rate
    Fast Mode up to 1 MHz (X1, Y1, X2, Y2, ADC1, Demod I/P 1, Demod I/P 2)
    Normal Mode 1 kHz
    Power Requirements Via external model PS0110 universal power supply
    Voltage 100 - 240 VAC
    Frequency 47 - 63 Hz
    Power 40 VA max
    Width Width 15½" (390 mm)
    Depth Depth 10" (250 mm)
    With feet With feet 3" (75 mm)
    Without feet Without feet 2½" (64 mm)
    Weight Weight 6.6 lb (3.0 kg)
    Model 7230/99 Increases upper reference frequency limit from 120 kHz to 250 kHz. Can be installed by firmware upgrade.
    Preliminary specifications subject to change without notice
  • Options +

    Item Model Number
    Extended Frequency Range-
    Extends the upper frequency limit from 120kHz to 250kHz
    Rack Mount K02006
  • Software +

    Item Model Number
    Acquire Software
    The software includes a powerful plotting engine that lets you show data just as you want it using a variety of line styles, allows data export to both text and CSV files, offers comprehensive clipboard support, and includes a context-sensitive help system
    Active X Control SRINSTCOMMS