Ludlum Measurements
Ludlum
Ludlum 9-4RF
Handheld survey meter
- Detector
- Air ionization chamber
- Weight with batteries
- 1.9 kg
10 referenced values
Bild: Ludlum
Ludlum 12SA
Handheld survey meter
Ludlum 12SA – handheld survey meter from Ludlum Measurements. Weight as specified: 2.1 kg including batteries.
- Detector
- NaI(Tl) scintillator, 2.5 × 2.5 cm (1 × 1 in.), internally mounted1
- 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 | NaI(Tl) scintillator, 2.5 × 2.5 cm (1 × 1 in.), internally mounted1 |
|---|
Performance
| Linearity | ±10 % of true reading1 |
|---|
Measuring range
| Energy response | Energy dependent1 |
|---|
Electronics & signal
| Detector bias | Adjustable from 200 to 1500 Vdc1 |
|---|
Power & battery
| Power supply | Two "D" cell batteries1 |
|---|---|
| Battery life and conditions | Exceeds 600 hours, may be checked on meter face1 |
Mechanical
| Dimensions (H × W × L) | 22.2 x 21.6 x 8.6 cm with handle1 |
|---|---|
| Weight as specified | 2.1 kg including batteries1 |
Environment & ratings
| Operating temperature | −20 to +50 °C (−4 to 122 °F); may be certified for operation from −40 to +65 °C (−40 to 150 °F)2 |
|---|
General
| Meter dial | 0–3 µR/hr, 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
- 2
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