Description

Specifications

Detector

Internal Halogen-quenched, uncompensated GM tube with thin mica window, 1.4-2.0 mg/cm2 areal density. Effective diameter of window is 45 mm (1.77 in.). Radiation symbol on front label and end panel marks the center of the detector.
Operating Range

mR/hr - .001 (1µR) to 100
CPM - 0 to 350,000
µSv/hr - .01 to 1000
CPS - 0 to 5000
Total Counts- 1 to 9,999,000 counts
Accuracy (Referenced to Cs137)
Typically ±15% from factory, ±10% with NIST Source Calibration
Energy Sensitivity

Detects Alpha down to 2 MeV. Detects Beta down to .16 MeV; typical detection efficiency at 1 MeV is
approx. 25%. Detects Gamma down to 10 KeV through the detector window. 3340 CPM/mR/hr (137Cs). Smallest detectable level for 125I is .02 µCi at contact.
Built-In Efficiencies

Sulfur (35S), Strontium (90Sr/y), Cesium (137Cs), Phosphorus (32P), Carbon (14C), Iodine (131I), Cobalt (60Co), and Alpha
Selectable Alert Set Range

mR/hr .001 - 50 and CPM 1 - 160,000. 70db @ 1m. Pulsating beeper sounds the alert. Adjustable alert levels are used for mR/hr / CPM, and µSv/hr / CPS. Alarm will sound when in Timer Mode when set alarm threshold is reached.
Anti-Saturation

Meter will hold at OVER RANGE in fields as high as 100 times the maximum reading.
Averaging Periods

Display updates every 3 seconds. At low background levels, the update is the average for the past 30-second time period. The timed period for the average decreases as the radiation level increases.

Display

Backlit 4 digit liquid crystal display with indicators.
Count Light

Red LED flashes with each radiation event.
Audio Indicator

Internally mounted beeper (can be switched off for silent operation)
Outputs

3.5mm jack for CMOS or TTL devices and counts to computer or datalogger.
USB for use with Free Observer USB Software for PCs
Power Requirements

One 9-volt alkaline battery (non-rechargable) or USB-AC Adapter. Battery life is approx. 1200 hours at normal background.
Temperature Range

-10ºC to 50ºC (14ºF to 122ºF)
Weight

273 g (9.6 oz.) without battery.
Size

150 x 80 x 30 mm (5.9 x 3.1 x 1.2 in.).
Includes

Carrying Case, Certification of Conformance, USB Cable, Observer USB Software
Options

Xtreme Boot, Wipe Test Plate, & Stand
Limited Warranty

1 year limited warranty