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Model 9-7

The Ludlum Model 9-7 Ion Chamber Display Unit is a digital readout and control unit that can be attached to any compatible ion chamber (sold separately). This instrument is a direct replacement for the discontinued Eberline Model RO-7, and will work with any of the existing Eberline RO-7 series detectors, extensions, and cables.

This instrument provides remote monitoring in high-range beta and gamma fields. The gamma measurement range is 0 to 19.99 kR/hr, covered by three separate detectors. The 9-7 automatically recognizes which detector is connected so no recalibration or adjustment is required when switching detectors. These ion chambers can either be connected directly to the instrument or via rigid extensions, flexible cables, or both, to accommodate the length required. The detectors will remain functional with extensions/cables up to 152 m (500 ft) in length.

The instrument display and controls are very similar to the original RO-7 to minimize any procedural changes or re-training. The backlit LCD display presents three large 127 mm (0.5 in.) sized characters together with a floating decimal point to indicate the measurement along the R/hr scale. When connected to the highest range detector, a separate kR/hr indicator is prominently illuminated to warn the operator of the higher scale in use. A rotary switch for selecting instrument On/Off and Battery Status, an LCD backlight switch, and  Zero Adjust knob are the extent of the external operator controls.

  • Display Range: 0 to 19.99 kR/hr
  • Available Detectors (sold separately): 
    • Low Range: 0.001 to 1.99 R/hr
    • Medium Range: 0.1 to 199.9 R/hr
    • High Range: 0.01 to 19.99 kR/hr
  • Direct Replacement for the Eberline Model RO-7
  • Adapts to Existing Eberline RO-7 Detectors
  • Design Improvements over RO-7:
    • Standard "D" Size Batteries
    • Separate Battery Compartment for Field Replacements
    • Eliminated Mechanical Switch
    • Backlit LCD
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