Model 3-97

Gamma survey

A meter with an internal scintillation detector and external energy-compensated GM detector for locating sources and measuring exposure rate.

Detectors: Internal NaI(Tl), 2.5 × 2.5 cm; external 44-38 energy-compensated GM1
Weight including batteries and detector: 2 kg1

Download product sheet (PDF)All values with references – for tender documents

Specifications checked against the manufacturer’s documents on 2026-10-16

Manufacturer’s product page (opens in a new tab)

Overview

Nuclear power & nuclear technology Defence, security & preparedness Emergency services & first response Environmental monitoring & radiation protection Industry & quality control

Key features

Internal NaI detector for sensitive searches.

Specifications

The number after each value refers to the source listed below. Values are as published by the manufacturer; the exact configuration is always confirmed in our quotation.

Detector

Detectors	Internal NaI(Tl), 2.5 × 2.5 cm; external 44-38 energy-compensated GM1

Performance

Linearity	±10 %2

Measuring range

Exposure-rate range	Internal: 0–3000 µR/hr; external: up to 200 mR/hr1
Response time (10–90%)	FAST 4 s; SLOW 22 s1

Connectivity & interface

Display	Analog; four ranges2
Detector connector	Series C; alternatives available1

Power & battery

Power supply	2 D batteries1
Battery life, typical	600 h (alkaline batteries)1

Mechanical

Dimensions with handle (H × W × L)	24.1 × 8.9 × 21.6 cm1

Environment & ratings

Operating temperature	−20 to +50 °C1

Ordering & accessories

Weight including batteries and detector	2 kg1

The data comes from the manufacturer’s published documents. Manufacturers may change specifications; the current configuration and performance are confirmed in the quotation.

Documents

PDFModel 3-97 Gamma Exposure & Count RatemeterDatasheet · Ludlum

Sources

The number after each value refers to the source listed below. Values are as published by the manufacturer; the exact configuration is always confirmed in our quotation.

1
Model 3-97 Gamma Exposure & Count Ratemeter
Publisher: Ludlum MeasurementsDatasheet p. 1, Specifications (DETECTORS); p. 1, Introduction; p. 1, Specifications (CONTROLS); p. 1, Specifications Checked 2026-10-16
2
Model 3-97 Gamma Survey Meter
Publisher: Ludlum MeasurementsProduct page Features; Specifications tab (Meter); Specifications tab (Linearity) Checked 2026-10-16