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Model 9-4RF

The Ludlum Model 9-4RF is a rugged air ionization chamber for performing beta-gamma dose rate measurements over a five-decade span ranging from 0 to 500 mSv/h (0 to 50,000 mR/hr). This variant of the Model 9-4 has improved components and shielding to pass RF susceptibility tests at military levels up to 18 GHz and is an improved replacement for old Model 440RF/D survey meters.

 

 

The ion chamber automatically compensates for changes in temperature and pressure. 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 selector switch selects Off, x10k, x1k, x100, x10 and x1. Other controls include an On/Off switch for a meter light, reset and battery test buttons, and a zero adjustment knob. An adjustable shoulder strap (included) provides a convenient and comfortable mode to carry the instrument during surveys.

The Model 9-4RF is equipped with a serial interface for calibration. An optional calibration kit supplies the necessary interface cable, software, calibration can, pressure pump, and serial-to-USB converter.

Features
  • 5-Range Ion Chamber
  • Ranges: 0 to 500 mSv/h (0 to 50,000 mR/hr)
  • 1000 mg/cm2 Retractable Beta Shield
  • RF Immunity
  • PC-Controlled Calibration
  • Low-Battery Warning
  • High-Background Zero Capability
  • Automatic Temperature & Pressure Compensation
  • Adjustable Shoulder Strap Included
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Related Products

Headphone Jack

This modification for survey meters adds a headphone jack to the instrument body so headphones can be used to monitor click-per-event audio and audio alarms. Headphones are helpful when the instrument is being used in areas with high ambient noise levels or in areas where the audio would be distracting to others, such as in a medical or office environment.

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Shoulder Strap

This 1.8 m (6 ft) adjustable shoulder strap is a great way to keep your hands free while operating survey meters. The nylon strap with a wide rubber comfort pad can also be helpful for conveying some of the heavier instrument/detector combinations in the field. 

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Model 3-IS NORM Kit
  • Ready-to-Go Kit in Rugged Case
  • Intrinsically Safe Analog Survey Meter
  • Measures Alpha, Beta, and Gamma Contamination
  • Includes:
    • Model 3-IS Intrinsically Safe Survey Meter
    • Model 44-9 Alpha-Beta-Gamma Detector
    • Model 44-2 High Energy Gamma Detector
    • Check Source, Cable, Batteries, Transport & Storage Case

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Model 14C-MERK
Medical Environment Response Kit
  • Model 14C Survey Meter
  • Model 44-2 Gamma Scintillator Detector
  • Model 44-9 Alpha-Beta-Gamma GM Detector
  • Model 25 Series Personal Radiation Monitor
  • Check Source and Holder
  • Rugged Case

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Model 2241-3MERK
Medical Environment Response Kit
  • Model 2241-3 Scaler-Ratemeter
  • Model 44-2 Gamma Scintillator Detector
  • Model 44-9 Alpha-Beta-Gamma GM Detector
  • Model 44-142 Beta Scintillator Detector
  • Model 25 Series Personal Radiation Monitor
  • Check Source and Holder
  • Rugged Case

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Model 3001-MERK
Medical Environment Response Kit
  • Model 3001 Survey Meter
  • Model 44-2 Gamma Scintillator Detector
  • Model 44-9 Alpha-Beta-Gamma GM Detector
  • Model 44-142 Beta Scintillator Detector
  • Model 25 Series Personal Radiation Monitor
  • Check Source
  • Rugged Case

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Model 14C-RK
Emergency Response Kit
  • Model 14C Survey Meter
  • Model 44-2 Gamma Scintillator Detector
  • Model 44-9 Alpha-Beta-Gamma GM Detector
  • Check Source and Holder
  • Rugged Case

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Cables

Ludlum offers straight cables with either type C, BNC, SHV, MHV, or UHF connectors. Unless specified otherwise, Ludlum survey meters and detectors are shipped with “C” type connectors. When a meter and accompanying probe are ordered as a matched set, Ludlum automatically includes a 99 cm (39 in.) straight-type cable with “C” connectors at no additional charge. (Note: We no longer offer coiled cables.)

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Model 3002/FM Series
Alpha-Beta Floor Monitor
  • Alpha-Beta Scintillation Detectors
  • Active Window Area: 400 or 1080 cm2 (62 or 167.4 in2)
  • 22.4, 40.9, or 65.7 cm (8.8, 16.1, or 25.9 in.) Wide Detection Path
  • Adjustable Detector Height

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Model 42-38
WENDI-2 Wide Energy Neutron Detector
  • Detector Type:
    • 3He Tube
    • Moderator: 22.9 cm (9 in.) dia.
  • Sensitivity (241Am/Be): 450 cpm per mrem/hr
  • Detection Range: Thermal to 5 GeV

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Model 78-9
Stretch Scope Survey Meter
  • Digital Meter
  • Extends to 3.6 m (12 ft.)
  • Pancake GM Detector

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Model 78-6
Stretch Scope Survey Meter
  • Analog + Digital Meter
  • Extends to 3.6 m (12 ft.)
  • NaI(Tl) Scintillator Detector
  • Range: 0.01 to 50 µSv/h (1 to 5000 µR/hr)

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Model 79/2
Stretch Scope Survey Meter
  • Digital Meter
  • Extends to 4.5 m (14.75 ft.)
  • Internal Energy-Compensated GM
  • Range: 0.001 mSv/h to 0.04 Sv/h (0.1 mR/hr to 4 R/hr)

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Model 79/1
Stretch Scope Survey Meter
  • Digital Meter
  • Extends to 4.5 m (14.75 ft.)
  • CsI(Tl) Scintillator Detector
  • Range: 0.01 µSv/h to 500 µSv/h (1 µR/hr to 50 mR/hr)

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Model 79
Stretch Scope Survey Meter
  • Digital Meter
  • Extends to 4.5 m (14.75 ft.)
  • Energy-Compensated GM Detector
  • Range: 10 µSv/h to 10 Sv/h (1 mR/hr to 1000 R/hr)

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