Ludlum Measurements
Ludlum
Ludlum 9-4RF
Handheld survey meter
- Detector
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- Weight with batteries
- 1.9 kg
10 referenced values
Bild: Ludlum
Ludlum 19A
Handheld survey meter
Ludlum 19A – handheld survey meter from Ludlum Measurements. Weight as specified: 2.1 kg including batteries.
- Detector (D × L)
- NaI(Tl) scintillator, 2.5 × 2.5 cm (1 × 1 in.), internally housed1
- Weight as specified
- 2.1 kg including batteries1
Download product sheet (PDF)All values with references – for tender documents
Specifications checked against the manufacturer’s documents on 2026-10-16
Overview
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
| Detector (D × L) | NaI(Tl) scintillator, 2.5 × 2.5 cm (1 × 1 in.), internally housed1 |
|---|
Performance
| Linearity | Reading ±10 % of true value1 |
|---|
Measuring range
| Sensitivity (¹³⁷Cs gamma) | Approximately 17,500 cpm per μSv/h (175 cpm per μR/hr)1 |
|---|---|
| Measurement range | Background to 500 µR/hr1 |
| Energy response | Energy dependent (energy response curve available from the manufacturer)1 |
Power & battery
| Power supply | 2 "D" cell batteries1 |
|---|---|
| Battery life and conditions | Typically 600 hours with alkaline batteries1 |
Mechanical
| Dimensions (H × W × L) | 19.8 x 8.9 x 21.6 cm with handle1 |
|---|---|
| Weight as specified | 2.1 kg including batteries1 |
Environment & ratings
| Operating temperature | -20 to 50 °C1 |
|---|
General
| Meter dial | 0–5 µSv/h (0–500 µR/hr), dual-coloured logarithmic scale, BAT TEST (other meter faces available)1 |
|---|
The data comes from the manufacturer’s published documents. Manufacturers may change specifications; the current configuration and performance are confirmed in the quotation.
Documents
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
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