The CDV-715 was the most widely produced of all the Civil Defense radiation instruments at a total of 567,457 instruments. Lionel, Victoreen and Landers Frary & Clark were the only manufacturers of the CDV-715. The CDV-715 showed up in 1961 or 1962.

CDV-715 is a high range gamma survey meter for general postattack operational use. The ranges of this instrument are 0-0.5, 0-5, 0-50 and 0-500 roentgens/hour.

When properly calibrated, the response of this instrument is within the range of plus or minus 20 percent of the true gamma radiation dose from a Cobalt 60 or Cesium 137 radioactive source.

This instrument was designed for use by radiological monitors for the major part of their operation in the period following an attack. The instrument is primarily for surface monitoring survey.

The instrument consists of a detecting element, power supply, electronic circuitry to amplify the minute current from the detector, and a indicating meter. The detecting element of the the CDV-715 is an ionization chamber.

Note that the detecting element is NOT a Geiger-Mueller tuve, but rather an ion chamber, of much lower sensitivity.
Ranges: 0.5, 5, 50 mR/h
Batteries: 4 D cells
Carrying strapp, Manual