This product appears in the PureSample Source Book Vol. 4 (ERE)
Overview
Same Monitor 4. New ergonomic design. The M4 and M4EC are compact, general purpose survey meters capable of detecting alpha, beta, gamma, and x-rays over 3 selectable ranges. A red count light flashes and a beep sounds with each event detected. The Monitor 4EC offers a more linear reading for gamma and x-rays (above 40 keV).
Detector
• Monitor 4: Halogen - quenched uncompensated GM tube with thin mica window 1.5 to 2.0 mg/cm2 thick
• Monitor 4EC: Halogen-quenched GM tube, energy compensated sidewall 2 mm tin filter. Thin mica window 1.5 to 2.0 mg/cm2 thick
• Display: Analog Meter holds full scale in fields as high as 100X max reading
• Operating Range: 0 to 50 mR/hr and 0 to 500, 0 to 5,000, 0 to 50,000 CPM or 0 to 500 μSv/hr
Monitor 4 Energy Sensitivity
• M4: Detects alpha down to 2.5 MeV; typical detection efficiency at 3.6 MeV > 80%. Detects beta at 50 keV with 35% efficiency. Detects beta at 150 keV with 75% efficiency. Detects gamma and x-rays down to 10 keV through the window, 40 keV minimum through the sidewall. Normal background is approximately 10 to 20 CPM.
• M4EC: Same as Monitor 4 except the energy response for gamma and x-rays through the detector sidewall is flat within +61% or -26% over the range of 40 keV to 100 keV, and within +35% or -17% over the range of 100 keV to 1.3 MeV.
• Gamma sensitivity: 1000 CPM/mR/hr (ref. to Cs-137)
• Range switch: X1, X10, X100, battery check
• Accuracy: ± 15% of full scale (referenced to Cs-137)
• Audio: internally mounted beeper (can be turned off for silent operation)
• Power requirements: 9 V alkaline battery up to 2,000 hrs at normal background
• Temperature range: -20° C to 55°C (-4°F to 131°F)
Weight
• M4: 223.9 g (7.2 oz) without battery
• M4EC: 245.7 g (7.9 oz) without battery
• Size: 8.25" x 2.75" x 1.875" (210 x 70 x 48 mm)
Includes carrying case with belt clip, observer software and mini-USB cable.
Accessories: SI Meter Option
Warranty: 1 year limited warranty
All meters above come with carrying case. Batteries not included.
Documents
Calibration and repair
Send it to our Montreal service team. We evaluate the instrument and send a detailed quote before any work starts.
Questions, answered
How fast will I get a price?
Send the quote request and a specialist replies within 4 business hours, Monday to Friday, 8:00 to 4:30 ET.
Can we pay on account or by purchase order?
Yes. With established credit, terms are Net 30 days, and you can send your purchase order with the quote request. We also accept Visa, Mastercard and American Express.
How is shipping charged?
On quotes and account orders, freight is F.O.B. Montréal: the carrier charge is worked out at shipment from the packed weight and dimensions, and added to your invoice. In-stock items can also be picked up the same day in Montréal (8605 rue du Champ-d'Eau).
Can I return it?
Yes, within 30 days of purchase, with a return authorization number from customer service first. A 25% restocking fee applies, unless it is a defect covered by the warranty. Special orders, hazardous materials, flammable liquids and gases can't be returned. Return policy
Can ERE calibrate or repair it?
Yes. Our Montréal service shop calibrates and repairs it in-house. Request service
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