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Model 9-3

The Ludlum 9-3 ion chamber is a rugged air ionization chamber for performing beta-gamma dose rate measurements over a five-decade span ranging from background to 500 mSv/h (50 R/hr). The chamber wall (including the instrument case) is 1000 mg/cm2. A 1000 mg/cm2 retractable beta shield allows beta measurement with a 7 mg/cm2 window. The six-position switch selects Off, x10k, x1k, x100, x10 and x1. Each range has a front-panel mounted calibration control. Other features include an audio output, reset, and zero adjust capabilities. Means are also provided to zero the electrometer leakage current.

An adjustable shoulder strap (included) provides a convenient and comfortable mode to carry the instrument during surveys.

  • 5 Ranges from Background to 500 mSv/h (50 R/hr)
  • 1000 mg/cm2 Retractable Beta Shield
  • Temperature Compensated
  • Low Battery Warning
  • High Background Zero Capability
  • Proportional Audio Output
  • Adjustable Shoulder Strap Included
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