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DSPEC LF Digital Signal Processing Gamma Ray Spectrometer

DSPEC LF Digital Signal Processing (DSP) based Gamm Ray Spectrometer for Germanium (HPGe) Radiation Detectors
  • Full-featured, digital spectrometer for HPGe and NaI detectors
  • Automatic optimization for best detector performance (patented)
  • ORTEC SMART-1™ intelligent HPGe support
  • Continuous display of detector status and state-of-health information
  • Fast data transfer for live spectrum display
  • Easy installation with true plug-and-play on USB 2.0
  • Excellent temperature and count rate stability
  • MAESTRO MCA Emulation Software included
  • Full computer control of every function

DSPEC LF is a member of the DSPEC USB family of digital technology gamma-ray spectrometers from ORTEC. It provides the same rock solid spectral stability with variation in temperature and count rate and retains many of the valuable attributes of the other two models. Many environmental and radiochemistry laboratories will find this instrument to be the best MCA for day-to-day sample counting with laboratory HPGe or NaI detector systems.
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  • More Information +

    Detector Interface Module (DIM) (SMART-1) (SMART-INTERFACE)SMART-1™ Support for Quality Data — all the time, every time
    ORTEC's unique SMART-1 detectors are indeed smart. They monitor and store the detector state-of-health (detector temperature, preamp power, bias over range, bias on/off state). A single check by the DSPEC LF will verify the detector is ready and remains ready to perform acquisition. During acquisition, the SMART-1 detector continually monitors the state-of-health (SOH) to ensure the integrity of the acquired data. At the end of acquisition a quick check of the SOH flag in the SMART-1 detector shows if any parameters deviated from specification during the measurement. This is vitally important for environmental samples that must be counted for long periods of time and regulatory-driven samples where data integrity is important.

    Another big advantage is the SMART-1 detectors have the recommended bias value preset at the factory. You no longer have to look through paperwork or for tags on the detector to find the right bias setting. Simply turn on the DSPEC LF and the SMART-1 detector automatically senses the detector temperature, determines the right high voltage bias, and turns it on.

    Fast PC Interface
    The DSPEC LF gives you high speed control over standard USB. The plug-and-play feature makes installation simple. A nearly unlimited number of DSPEC LFs can be connected simultaneously using USB hubs. As an ORTEC CONNECTIONS compatible instrument, the DSPEC LF works in a networked and in a stand-alone configuration. ORTEC CONNECTIONS means: any hardware, any software, anywhere in the laboratory with full seamless control and built-in security.

    Simple, Single-Cable Connection to Detectors
    The DSPEC LF uses the unique ORTEC DIM (Detector Interface Module) to connect the DSPEC LF and the detector with only a single cable. The DIM provides for bias close to the detector so that only signal and low voltage power are carried in the cable. No longer is high voltage bias and the dangers associated with it carried over long distances.

    Monitor Vital Values
    The DSPEC LF shows the values you need on the front panel LCD display. The DSPEC LF displays the instrument ID, name, serial number, preset count conditions, current live and real time, dead time percentage, input count rate, HV status and value, and the serial number for SMART-1 detectors.

    Small Size
    Smaller than a sheet of paper, the DSPEC LF sits right on the desktop. Lightweight and rugged, multiple DSPEC LFs can be stacked on top of one another via their interlocking cases without fear of sliding or tipping. 

    Mix-and-Match with Your Existing MCBs
    ORTEC CONNECTIONS software supports any combination and number of USB devices connected to any computer. For example, two digiDARTs may be combined with two DSPEC LFs connected to the same PC using a USB hub. And any number of other ORTEC MCBs can be connected to the same system by network, printer port, RS-232, or Dual Port Memory.
  • Specifications +

    240 x 160 pixel backlit LCD provides status information, instrument ID, bias information, live and real time.
    Concurrent Connections Limited by the computer and supporting USB hubs. ORTEC CONNECTIONS software supports up to 127 USB-connected devices per computer.
    System Gain Settings • Coarse Gain: 1, 2, 4, 8, 16, or 32.
    • Fine Gain: 0.45 to 1.
    • The available range of gain settings supports all types of HPGe detectors. Specifically the following maximum energy values are achievable using the standard ORTEC preamplifier (max gain to min gain):
    COAX  187 keV to 12 MeV
    LO-AX 94 keV to 6 MeV
    GLP/SLP     16.5 keV to 1 MeV

    Preamplifiers Computer selectable as either resistive or TRP preamplifier.
    System Conversion Gain The system conversion gain is software controlled from 512 to 16k channels.
    Digital Filter Shaping Time Constants • Rise Times: 0.8 µs to 23 µs in steps of 0.2 µs.
    • Flat Tops: 0.3 to 2.4 in steps of 0.1 µs.
    Dead Time Correction Extended live-time correction according to Gedcke-Hale method.
    Accuracy Area of reference peak changes <±3% from 0 to 50,000 counts per second.
    Linearity • Integral Nonlinearity: <±0.025% over top 99.5% of spectrum, measured with a mixed source (55Fe @ 5.9 keV to 88Y @ 1836 keV).
    • Differential Nonlinearity: <±1% (measured with a BNC pulser and ramp generator) over top 99% of range.
    • Digital Spectrum Stabilizer: Controlled via computer, stabilizes gain and zero errors.
    System Temperature Coefficient • Gain: <50 ppm/°C. [Typically <30 ppm/°C.]
    • Offset: <3 ppm/°C of full scale, with Rise and Fall times of 12 µs, and Flat Top of 1 µs. (Similar to analog 6 µs shaping.)
    Maximum System Throughput >100,000 cps.
    Pulse Pile Up Rejector Automatically set threshold.
    Automatic Pole Zero Adjustment Computer controlled. Can be set automatically or manually. Remote diagnostics via InSight Oscilloscope mode. (Patented.)
    Digital Gated Baseline Restorer Computer controlled adjustment of the restorer rate (High, Low, and Auto). (Patented.)
    LLD Digital lower level discriminator set in channels. Hard cutoff of data in channels below the LLD setting.
    ULD Digital upper level discriminator set in channels. Hard cutoff of data in channels above the ULD setting.
    Rate Meter Count-rate display on MCA and/or PC screen.
    Battery Internal battery-backed up memory to maintain settings in the event of a power interruption.

    Inputs and Outputs
    Multi pin connector (13W3) with the following:
    • Preamp Power: 1 W maximum (+12 V, –12 V, +24 V,  –24 V, 2 GND).
    • Amp In: Normal amplifier input.
    • TRP Inhibit.
    • Power for SMART-1 or DIM.
    • Control of HV and SMART-1 Detector (2 wires).
    USB Universal serial bus for PC communications.
    Power Connection to supply power from a wall mounted dc supply. (+12 V dc <1.25 A).

    Electrical and Mechanical

    Dimensions 8.1 H x 20.3 W x 24.9 D cm   (3.2 H x 8 W x 9.8 D in.)
    Weight 1.0 kg (2.2 lb)
    Operating Temperature Range 0 to 50°C, including LCD display.

    Radiation Detector High Voltage Supplies
    HV module is integral with the radiation detector itself.
    non-SMART-1 For “legacy” or “non-SMART-1” detectors, the HV supply is in the form of a Detector Interface Module or “DIM” with 2 m cables. The DIM has a mating connector for the traditional detector cable set: 9-pin D preamp power cable, Analog In, Shutdown In, Bias Out, and Inhibit In.

    DIMS for non-SMART-1 detectors are available with the following high voltage options:
    • DIM-POSGE: Detector Interface Module for ANY Non-SMART-1 positive bias HPGe detector.
    • DIM-NEGGE: Detector Interface Module for ANY Non-SMART-1 negative bias HPGe detector.
    • DIM-POSNAI: Detector Interface Module for ANY positive bias NaI detector.
    • DIM-296: Detector Interface Module with Model 296 ScintiPack tube base/preamplifier/bias supply for NaI detectors with 14-pin, 10 stage photomultiplier tubes.
    Front Panel Display
    In all cases, Bias Voltage Setting and Shutdown polarity are set from the computer. The DSPEC LF can monitor the output voltage and shutdown state; Detector high voltage value (read only); and Detector high voltage state (on/off) (read/write) which are displayed on the front panel LCD. In addition, the SMART-1 detector provides additional state-of-health information by monitoring the following functions: Detector element temperature (read only); Detector overload state; Detector authentication code (read/write); and Detector serial number (read only).
  • Ordering Information +

    Model Description
    DSPEC LF DSPEC LF with MAESTRO Software, No DIM, for use with SMART-1 equipped detector.
    DSPEC LF-POSGE      DSPEC LF with MAESTRO Software and DIM-POSGE for use with Non-SMART-1 detector.
    DSPEC LF-NEGGE DSPEC LF with MAESTRO Software and DIM-NEGGE for use with Non-SMART-1 detector.
    DSPEC LF-POSNA DSPEC LF with MAESTRO Software and DIM-POSNAI for use with NaI detector.
    DSPEC LF-296 DSPEC LF with MAESTRO Software and DIM-296 for use with NaI detector.
    Additional DIMs  
    DIM-POSGE Detector Interface Module for ANY Non-SMART positive bias HPGe detector
    DIM-NEGGE Detector Interface Module for ANY Non-SMART negative bias HPGe detector
    DIM-POSNAI Detector Interface Module for ANY positive bias NaI detector
    DIM-296 Detector Interface Module with Model 296 ScintiPack tube base/preamplifier/bias supply for NaI detectors with 14-pin, 10 stage photomultiplier tubes.