The ORTEC DigiDART is an extraordinary, portable, HPGe-grade Multichannel Analyzer. It has been carefully engineered to perform the most demanding real world, PORTABLE gamma-ray spectroscopy applications. The entire design, from the on-board display to the package ergonomics, answers the needs of people like you — leading practitioners of in-field spectroscopy.
As you expect from ORTEC, the DigiDART is an advanced, all-digital design, with three ORTEC-held patents — clearly advancing the state of the art for portable MCAs.
Weighing less than 1160 grams, the DigiDART is an attractive, light-weight instrument; easy to handle, and RUGGED. The case is molded ABS — the same strong plastic used extensively in automobiles. The outside is coated with a shock-absorbing, easy-grip, stay-clean coating — just like your other tools. The display and keypad are recessed to protect them when the instrument is dropped. The connectors are all on one side and recessed for protection. The battery is inside — again for added protection and covered with a splash-proof door. It can be charged in place, even when the DigiDART is operating. The battery is truly integrated into the rugged DigiDART and not simply clipped on the back panel; exposed and easy to break. Changing the battery is simple: just open the door and replace.
DigiDART Display and Keypad
Naturally, the DigiDART is entirely computer controllable; but with the built-in display and numeric keypad, it is a DRAMATIC advance from the current generation of portable MCAs. This high-quality display and easy to use keypad mean it can perform a variety of tasks without an attached PC.
For in-field applications, a PC is difficult to carry and operate, but without a display you can't see the spectrum or results. The DigiDART's built-in, backlit LCD display panel and keypad provide the confidence you need that your data is good. A clear spectral display is provided and start/stop control is accomplished simply by a single keypad entry.
The spectral Display of the DigiDART is patterned after ORTEC's very successful MAESTRO MCA Emulator (ask for the MAESTRO brochure), in use on thousands of systems worldwide. A 240 x 160 pixel LCD display allows the user to monitor acquisitions and instrument settings status, with no attached PC. It features a live spectral display with region of interest, peak information and on line activity calculations. ROIs are shown as a bar below the spectrum.
Real Time Activity Calculations . . . NO PC Required!
DigiDART can also perform nuclide ID and activity calculations using internally stored calibration information, at the touch of a button, and all without the use of an attached PC. Everything is user controlled: the library for analysis, displayed peak labels, unit labels and calibration parameters. They are all easily downloaded by MAESTRO to the DigiDART, but they can be changed in-field to adapt to your changing needs. Activity is calculated for the list of up to 9 nuclides. The spectral data can be saved and later re-analyzed in more detail using a more sophisticated PC-based analysis package such as GammaVision.
All of the DigiDART screens and operations are set using the keypad and the display. The operation is simple — select what you want from the displayed list by number and the Enter key. The main groups are: View Status, Enter ID, Nuclide ROI contents, Peak Info, Select ROIs, Select Status contents, Adjust controls, general settings and View memory contents. The complete list of all functions is given in the specification section.
Using the keypad and the display, the MCA settings can be verified or changed in the field without a host computer.
Protection of the data is important, so the MENUS have password protection. The operations are separated into two groups: USER and ADMINISTRATOR. The USER password protects the instrument from unauthorized use. That is, you can protect your data stored in the internal memory. The ADMIN or Setup functions are protected by a different administrator password. The ADMIN functions can only be changed by the Administrator ensuring that your results are based on the correct parameters.
SMART-1 HPGe Radiation Detector Support
ORTEC's SMART-1 detector technology is a great advance in HPGe Radiation detectors and their operation. SMART-1 technology is a major enhancement to data and chain of custody integrity. It is a dramatic improvement in detector management practice and data control.
A SMART-1 HPGe detector is intelligent. The built-in controller monitors and reports on all vital system functions. Individual vital signs are available as well as the overall "state of health." The detector controller knows who it is: each unit has its own identification serial number. To further increase data integrity, the controller can even store authentication codes and later return the code to ensure traceability of the data.
DigiDART uses the special SMART-1 "state of health" (SOH) function to verify that the detector was operating properly for the entire data collection time. When the acquisition is started, DigiDART clears the SOH register in the SMART-1 controller. During data acquisition, the SMART-1 detector monitors all of its own "vital functions." Should any of the monitored functions fall outside a specified range of values (even if they subsequently return to normal), the condition is registered and at the end of the acquisition the DigiDART reads the SOH and displays a warning message if a problem was detected. No Message — no problem. The SOH status is saved with the spectral data in the SPC file as part of the QA process. Any CONNECTIONS program, (ask for the ORTEC CONNECTIONS brochure), even user-developed packages, may read the SOH register through the DigiDART for maintaining the spectrum QA.
Authentication using the SMART-1 Radiation Detector
The DigiDART/SMART-1 combination also guarantees spectrum authenticity. At the start of the acquisition, the DigiDART reads the SMART-1 detector serial number. The DigiDART generates a random number and writes it to the SMART-1 detector. At the end of the acquisition, the DigiDART reads both numbers from the SMART-1 detector and compares the "stop" values to the "start" values. An exact match assures data integrity. Because DigiDART, like all ORTEC MCA products, forms part of the CONNECTIONS architecture, these operations may be carried out remotely over a network, making DigiDART IDEAL for unattended monitoring applications. The combination of the DigiDART and a SMART-1 detector is all that is required to provide full functionality and traceability. The SMART-1 detector includes the module shown in the figure which houses the HV and the detector controller. The cables are captive, strain-relieved and sealed against water penetration, eliminating the high voltage connectors and all the problems of HV connectors.
Detector Interface Modules for non-SMART-1 HPGe Radiation Detectors
For older, non-SMART-1 detectors a DigiDART system is completed with a Detector Interface Module (DIM). The DIM includes the HV, controlled from the DigiDART, and connects to the "usual" detector connections for preamplifier and high voltage. DIMs are available for all types of detectors used with the DigiDART. The DIM connects to the DigiDART with a single cable.