Features
- Neutron Detector with Removable Moderator
- Alpha-Beta-Gamma GM Detector
- Rugged
- 4-Range Analog Ratemeter
The Ludlum Model 15 detects and measures alphas, betas, gammas, and neutrons. A GM detector can be selected by the user to obtain alpha-beta-gamma readings. The neutron count rate measurement is provided by a 3He proportional detector that is outfitted with a removable moderator.
The ratemeter is a four-decade, analog meter designed with a cast aluminum instrument housing, incorporating a separate battery compartment and accompanying metal handle. This design delivers industrial robustness and quality, promoting long-lasting protection and instrument life. The front-panel controls include a rotary switch for selecting the four-decade range, instrument shut-off, and battery test; an audio on/off switch; a fast/slow response switch; a GM/Neutron Detector switch; a count reset; and high-voltage test pushbutton. The Model 15 is a complete turn-key system and includes two "D" cell batteries.
| Indicated Use | Alpha, beta, gamma, neutron detection |
|---|---|
| Neutron Detector (Model 42-14H) |
Detector Type: 2 atm 3He proportional detector with 7.6 cm (3 in.) diameter, cadmium-lined (removable) moderator for thermal neutrons Sensitivity (bare 241AmBe): 55 cpm per mrem/hr Detection Range: Thermal to approximately 12 MeV Energy Response: Not linear through energy spectrum (0.025 to 12.0 MeV) Gamma Rejection (137Cs gamma): < 10 cpm through 10 R/hr |
| Alpha-Beta-Gamma Detector (Model 44-7) |
Detector Type: Thin end-window GM detector Window: 2.0 ± 0.3 mg/cm2 mica Window Area: Active: 6.4 cm2 (1 in2); Open: 5.2 cm2 (0.8 in2) Efficiency (4π): 14C: 2%, 90Sr/90Y: 10%, 99Tc: 7%, 239Pu: 7% Sensitivity (137Cs gamma): Typically 2100 cpm per mR/hr Energy Response: Energy dependent Background: Approximately 40 cpm |
| Instrument Range | 0 to 500,000 cpm |
| Linearity | ± 10% of true value |
| Meter Dial | 0 - 500 cpm, 0 - 2.5 kV, BAT TEST (Meter Faces tab lists other available meter faces) |
| Meter | 6.4 cm (2.5 in.) arc, pivot-and-jewel suspension |
| Controls |
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| Audio | Built-in unimorph speaker with on/off switch, greater than 60 dB at 61 cm (2 ft.) |
| Working Environment | Normal working conditions |
| Temperature Range | -20 to 50 °C (-4 to 122 °F) |
| Power | 2 each "D" cell batteries, housed in sealed compartment that is externally accessible |
| Battery Life | Approximately 600 hours with alkaline batteries, can be checked on meter |
| Connector | Series "C" |
| Size (H x W x L) | 31.8 x 8.9 x 21.6 cm (12.5 x 3.5 x 8.5 in.) |
| Weight | 3.7 kg (8.1 lb) |