DSM-502 Digital Geiger Counter

DSM-502 Survey Meter by WB Johnson

Internal G-M probe for Medium Range Dose: 0-2,000 mR/hr

The DSM-502 Survey Meter features an internal G-M probe for medium range gamma radiation detection. The large digital display reads in dose rate (mR/hr) and counts (cpm). A scaler function is included as well. The response time is adjustable in fast and slow modes. An optional data output port is available upon request. The DSM-502 is a noteworthy improvement over the older analog geiger counters.

DSM-502 Operation Manual

DSM-502 Specifications

Input Sensitivity: 0.05V
Display: LCD 4-Digit x 0.75 inch LCD with LED Back light
LCD Refresh Rate: 0.8 - 3.0 Seconds in 0.2 Second increments - adjustable
Display Back light: Push button, 30 Second auto off
Dose Ranges: 0.01-2,000 mR/hr
CPM Ranges: 0-999.9 Kcpm
Probe Linearization: Internal adjust for cal constant and dead time
Scaler Ranges: 0-999.9 Kcpm
Scaler Count Time Ranges: 10-2550 Seconds (10 second increments)
Alarms: 5-95% of Range
Diagnostics: Low Battery, Over range - audible and visual
Range Adjustment: Auto-Ranging All Scales
Electrical Non-Linearity: < 5%
Response Time: Fast 10-2550 Seconds (adjustable) | Slow 10-250 seconds (adjustable)
Drift: <5%
Environmental: -20° F[-28° C]-140° F[60° C] | 5-95% RH IPX4 Housing
High Voltage Adjustable: 300-1500 VDC|Regulation +-1%
Battery: 6 "AA" Alkaline-400 hours nominal
Circuitry: Digital Microprocessor Controlled
Dimensions: 5.25 inches (14cm) Height x 4 inches (10cm) Width x 7 inches (18cm) Length
Weight: 2.5 lbs. (1.2 Kilos)
Construction: Heavy Duty Cast Aluminum and Stainless Steel
Probes: Internal Energy Compensated Geiger Mueller tube