GM-10 / GM-45 / GM-90 Detectors

The difference between the two models is the size of the tube - the GM-45 has a much larger surface area tube (over 23 times as large). This means that it can detect many more particles, giving a better reading. Vist the Specs page for a full comparison. Also be sure to visit our page comparing the readings between the GM-10 and GM-45.

The newly available GM-90 has two pancake detector tubes, for twice the sensitivity of the GM-45!

By adding up the number of detections per minute, the Counts Per Minute (CPM) is calculated and displayed. This number is a relative indicator of the amount of radiation present.

Due to various sources of radiation, both man-made (fallout from nuclear testing in the 1950's and 1960's) and natural (such as radon, cosmic rays, and the like), there is always some background radiation present.

This background radiation level varies, depending on your location, and even the local weather. There are also short term statistical variations. This means that the CPM will vary over a short period of time, centered over what can be considered the actual average value.

Since the GM-10 and GM-45 are self powered by the computer's serial port, no batteries or external power adapters are needed! You can operate them anywhere you can take your computer or laptap!

Click on an image below for a larger picture:

GM-10:

A USB version of the GM-10 is also available:

GM-45:

GM-45 USB:

GM-90:

GM-90 USB: