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α/β detector ADC-1121 measures Alpha and Beta (and Gamma) radiation with high accuracy.
The 2 switches on the grip enable data-saving and time-constant changing, while directing it to the target.
This detector is connectable with TDC-9111.



Radiation Detected Alpha, Beta (and Gamma)
Detector ZnS (Ag) Scintillator + Plastic Scintillator
Detection area 100cm2
Instrument Efficiency α : 35%/2π±25%, and more than 30%/2π (30%/2π to 43.7%/2π) by 241Am
β : 40%/2π±25% (30%/2π to 50%/2π) by 36Cl
* 0.5cm between detector and source
Counting Rate Range α : 0 to 10ks-1, 0 to 100kmin-1
β : 0 to 10ks-1, 0 to 300kmin-1 (Reading in Bq/cm2 on TDC-9111)
Others Switches to change time constant and save data, and LED lights
Weight Approx. 320 g (excluding cable and protection cover)


Connectable Detectors α/β detector, β detector, γ detector.
Radiation types are automatically identified when detector is connected.
Display Black and white LCD (with backlight and touch panel)
Display Mode Detailed, simplified, time-series, scaler, preset list and user settings
Displayed Contents Measurement value (digital and bar graph), measurement unit,
radiation type, time, time constant, battery level, peak hold value
and overload, etc.
Sound Alarm, measurement count
Alarm Settings: α, β and γ can be individually set
Display: alarm, sound simultaneously with LED flashing
Alarm Clear AUTO: Automatic clear when the value is under preset
HOLD: Alarming until RESET switch is pressed
Scaler Mode Preset time: 1 to 9,999 sec (999,999 counts at max by selecting 0)
Repeat time: 5 times at max
Earphone Earphone adapter socket for Micro USB is required
Data Saving Instantaneous value at any time or at preset intervals
144,000 data (in case of 100-day measurement at 60-second intervals)
100 folders can be created at max
Output USB2.0, Mass storage class
Power Primary battery: 8 AA alkaline batteries
Secondary battery: 8 AA NiMH batteries
USB supply (USB2.0)
Battery Life Connecting ADC-1121
Primary battery: 100 hours or longer (by new batteries at 20 degrees C)
Secondary battery: 70 hours or longer (by full-charged batteries at 20 degrees C)
Environmental requirements in
Temperature : -20 to +50 degrees C
Humidity : 90%RH or less (Non-condensing)
Dimensions Approx. 10 (W) x 19 (D) x 8.5 (H) cm
(excluding handle and protrusions)
Weight Approx. 740g (including batteries, and excluding detector and cable)

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Please note that all descriptions in this website conform to the Pharmaceutical and Medical Device Act in Japan as well as other laws and regulations in Japan. Model names, specifications and configurations of products in overseas market outside Japan may be different by the countries.