Ludlum Model 9-3

  Five Range Radiation Ion Chamber

Features

• 5 Ranges from Background to 50 R/hr

• 1000 mg/cm² Retractable Beta Shield

• Temperature Compensated

• Low Battery Warning

• High Background Zero Capability

• Proportional Audio Output

Introduction

The Ludlum 9-3 ion chamber is a rugged air ionization chamber for performing beta-gamma radiation dose rate measurements over a 5 decade span ranging from background to 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 selector 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.

Specifications

PART NUMBER: 48-3633

DETECTOR
Range: Typically 0.2 - 50,000 mR/hr
Linearity: Reading within 10% of true value
Energy Response: Within plus or minus 20% of true value from 10 keV - 2 MeV
Response Time : Approximately 5 seconds for 90% of final meter deflection on the x1 and x10 scales, and 3 seconds on the x100, x1k and x10k scales
Chamber Volume: 220 cm³
Window: 7 mg/cm² aluminized mylar
Window Area: 40 cm² (31.5 cm² open with optional 79% open screen)
Chamber Construction: Carbon coated acrylic
Beta Shield: Retractable 1000 mg/cm² phenolic slide
Side Wall: 1000 mg/cm² aluminum and acrylic

INSTRUMENT CONTROLS
Range Selection: x1, x10, x100, x1k, x10k, plus instrument off
Reset: Causes the chamber to discharge in order to re-establish a current reading
Battery: Pushbutton used to check battery capacity
Zero Adjust: 1 turn potentiometer to compensate for electrometer drift and limited background subtraction
Audio: On/Off
Calibration Controls: Individual potentiometers for each range; accessible from the front cover while in operational status

METER: 2.5” (6.4 cm) arc, 1 mA, pivot-and jewel suspension
METER DIAL: 0 - 5 mR/hr, BAT TEST
AUDIO: Built in unimorph speaker with ON/OFF switch
POWER: 2 each “AA” cell batteries housed in a sealed externally-accessible compartment
BATTERY LIFE: X1, X10 scales - 500 hours, X100 thru X10K scales - 100 hours. Wall voltage on with instrument shut off is approximately 6 months
CONSTRUCTION: Cast and drawn aluminum with beige powder-coating
TEMPERATURE RANGE: -4° to 122°F (-20° to 50°C). Temperature compensation maintains calibration within 15% of 25°C reading
SIZE: 9.2”H X 3.5”W X 8.5”L (23.4 X 8.9 X 21.6 cm) including instrument handle
WEIGHT: 3.6 lbs (1.6 kg) including batteries

This Product is CE Certified

Meter Face

Options

Technical Information

• Model 9-3 Data Sheet

• Model 9-3 Manual

• Model 9-3  to RO-20 Comparison Chart

• Model 9-3 Calibration Procedure

• Model 9-3 CE Certificate

• Model 9-3 Energy Response Test

• Model 9-3 Energy Test - K&S Associates

• Model 9-3 ANSI N42.17A Test Report - Geotropism and Photon Radiation Overload

• Model 9-4 ANSI N42.17A Testing

• Model 9-4 Angular Response Testing

• Model 9 CE Test Report

• Model 9 Altitude Dependence Chart

Alternate Instrument

• Model 9-4 - Same as Model 9-3 less audio output with added pressure compensation and PC controlled calibration.