Model 2401-P Dose

Pancake GM Pocket-Size Survey Meter with Dose Filter

Part Number: 48-3884

Features

• Self-contained Survey Instrument
• Integrated GM Pancake Detector
• Sliding Dose Equivalent Filter
• Convenient Handle Pivots for Storage
• Water, Dust, & Crush Resistant Case
• Simple to Use
• Low Cost
• Rugged

The Model 2401-P Dose instrument is a general purpose, self-contained, pocket-sized radiation detection meter designed around the venerable GM pancake detector. A simple switch allows the user to choose among the three range multipliers. Another switch selects between QUIET (click-per-event audio off), NORMAL, BAT CHECK, or OFF. The detector is conveniently packaged inside the instrument, and has a protective screen window. The included dose equivalent filter allows users to take more accurate dose measurements (see below). A convenient L-shaped stainless steel handle provides a secure and comfortable grip when using the Model 2401-P as a survey meter. Loosening the knob permits the handle to pivot, allowing the instrument to be easily housed in the included carrying and storage case. This instrument is available with several meter face options for measuring contamination and dose rate.

Sliding Dose Equivalent Filter

The GM pancake detector has a significant over-response to gamma energies between 20 - 150 keV, which produces dose measurement errors. To counteract this, Ludlum Measurements developed a sliding filter for the Model 2401-P GM pancake dectector that flattens the response to within 20% referenced to 137Cs (662 keV) over an energy range of 20 keV to 1.2 MeV. The Model 2401-P DOSE includes this filter.

• Specifications
• Meter Faces
• Documents

• Specifications
• Meter Faces
• Documents

Specifications

Indicated Use	Alpha, Beta, Gamma survey
Detector	15.51 cm2 (2.4 in2) pancake GM
Sensitivity (137Cs gamma)	Typically 3300 cpm per mR/hr
Efficiency	14C: 5% 90Sr/90Y: 22% 99Tc: 19% 99mTc: < 1% 32P: 32% 239Pu: 15%
Energy Response	With Dose Filter: Energy compensated for gamma and x-ray Without Dose Filter: Energy dependent
Meter Dial	See Meter Faces tab for available options
Multipliers	x1, x10, and x100
Response Time	Typically 11 s from 10% to 90% of final reading
Alarm	No
Audio	Click-per-event, may be turned off by moving selector to QUIET position
Power	9 volt battery
Battery Life	Typically 250 hours with alkaline battery
Construction	Cast and drawn aluminum with membrane panel
Size (H x W x L)	4.6 x 8.4 x 13.5 cm (1.8 x 3.3 x 5.3 in.)
Weight	0.4 kg (0.9 lb), including battery
Case	Model 2401 Series Hard Case

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Meter Faces

These tables list the most commonly used meter faces.

Dose Rate Meter Faces

Meter Face	Image (click to view larger)	Description
202-994		0 - 0.15 mR/hr BAT OK
202-999		0 - 1.5 µSv/h BAT OK

Count Rate / Dose Rate Meter Faces

Meter Face	Image (click to view larger)	Description
202-850		0 - 6.6 kcpm 0 - 2 mR/hr BAT OK
202-857		0 - 500 cpm 0 - 0.15 mR/hr BAT OK
202-1038		0 - 6.6 kcpm 0 - 20 µSv/h BAT OK
202-1106		0 - 500 cpm 0 - 1.5 µS/hr BAT OK
202-872		0 - 10 cps 0 - 1.9 µSv/h BAT OK

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Documents

• Data Sheet
• Product Manual

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