CD V-751X Dosimeter Charger (ca. 1965)
The CD V-751X was the prototype of a civil defense dosimeter charger that didn't require batteries. It did have a 1.5 volt "D cell" for the small light bulb that illuminated the dosimeter scale, but it wasn't necessary for the charger's operation. As can be seen in the photograph below, there is a plastic window at the corner of the charger that would allow ambient light to illuminate the scale even if the light bulb were not working.
The charge for the dosimeter is created by stressing a piezoelectric crystal. The stress is created by turning the aluminum lever on the top of the unit. In pictured device, the tension is applied with a piece of a mattress spring that the inventor, Stanley Kronenberg, found on his way to work one morning. Although this design never went into production, Kronenberg did patent it (US Patent 4,247,775). A brief description of the CD V-751X is found in the 1966 version of the List of Military and Civil Defense Radiac Devices.
Donated by the Federal Emergency Management Agency courtesy of Carl Siebentritt.
- Carl Siebentritt and Marlow Stangler personal communication.
- Kronenberg, S. Piezoelectric Dosimeter Charger, U.S. Patent 4,247,775 Jan. 27, 1981.
- Defense Atomic Support Agency List of Military and Civil Defense Radiac Devices DASA 1243 revised, 1966.