• Radiation Alert® Ranger

    The Ranger EXP features built in isotope efficiencies, download your data from the internal memory, great sensitivity, backlit display, timer and an external probe for hard to reach locations.

The Ranger EXP / External Probe - a ß y x


The Ranger EXP offers maximum performance in a lightweight, rugged solution for using your survey meter in the field. The Ranger EXP is designed specifically for individuals operating in tough environments. The small, handheld unit offers excellent sensitivity to low levels of alpha, beta, gamma, and x-rays. The digital readout is displayed with a red count light and a beeper sounds with each count detected. Other features include an adjustable timer, selectable alert, and with the free Observer USB Software Family, you can download your collected data, and set alarms!
Ranger EXP Quick Specs


RAP-RS2 Probe - External Halogen-quenched, uncompensated GM tube with thin mica window, 1.4-2.0 mg/cm2 areal density. Effective diameter of window is 45 mm (1.75 in.).

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 - 100 and CPM 1 - 350,000. 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.


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.
Energy Response Curve


Graphic LCD with Backlight

Count Light

Red LED flashes with each radiation event.

Audio Indicator

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


USB for use with Free Observer USB Software Family

Power Requirements

Two AA alkaline batteries (included). Approx. 800 hrs @ background


140 X 68 X 33 mm (5.5 X 2.7 X 1.3 in.)
Probe: 260 X 70 X 25 mm (10.25 X 2.75 X 1 in.)


20 oz (1.25 lbs.)


RAP-RS2 External GM Probe, 3 ft BNC Cable, Carrying Case, Xtreme Boot, Lanyard, Stand, Batteries, Mini-USB Cable, Observer USB Software Download, Certificate of Conformance


NIST Calibration

Limited Warranty

1 year limited warranty


Operation Manual English | Spanish | HTML Version | Ranger EXP Quick Specs | Frequently Asked Questions

Monitor 200
The Ranger
The Ranger EXP
Monitor 1000EC
a ß y x y x
Internal Memory
Included Protective Boot
Included Stand
Built-In Isotope Efficiences    
GM Detector Internal Internal External (EXP) Internal
mR/hr .001(1µR) to 200 .001(1µR) to 100 .001 (1µR) to 1000 mR/hr
µSv/hr - .01 to 2000 .01 to 1000 .01 to 10000
mSv/hr n/a n/a 0.00001 to 1
Counts Per Minute 0 to 214,000 0 to 350,000 0 to 450,000
Counts per Second 0 to 3575 0 to 5000 0 to 7500
Total Timed Counts 1 to 9,999,000

Accessories / For The Ranger EXP Radiation Detector, Survey Meter, and Geiger Counter

Ranger EXP Carrying Case


Reviews / Comments and Feedback

Similar Radiation Alert Detectors, Geiger Counter, and Survey Meters

  • Ranger EXP Geiger Counter Radiation Survey Meter
  • Monitor 200 Geiger Counter
  • Radiation Frisker - Geiger Counter Radiation Survey Meter