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Monitor 4
Specifications
Detector
Monitor 4: Halogen-quenched uncompensated GM tube with thin mica window
1.5-2.0 mg/cm2 thick.
Display
Analog Meter holds full scale in fields as high as 100X maximum reading.
CPM/mR/hr scale default. Optional SI Meter Scale option available upon request.
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 10-20
CPM.
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| Monitor 4 End Window | USB Port on Side of Unit |
|
Operating Range |
Monitor 4USB and Monitor 4ECUSB with Mini USB port |
|
0-.5, 0-5, 0-50 mR/hr |
The M4 and M4EC with Mini USB port on side are compact,
ergonomic, 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). |