3T* 
 
 MDDC-884 
 
 UNITED STATES 
 ^ ATOMIC ENERGY COMMISSION 
 
 f 
 
 OAK RIDGE 
 
 TENNESSEE 
 
 AN INTEGRATION RADIATION METER FOR BETA AND GAMMA RAYS, 
 SIGMION, MARK 10, MODEL 70 
 
 Argonne National Laboratory 
 
 Published for use within the Atomic Energy Commission. Inquiries for additional copies 
 and any questions regarding reproduction by recipients of this document may be referred 
 to the Technical Information Division, Atomic Energy Commission, P. O. Box E, Oak Ridge, 
 Tennessee. 
 
 Inasmuch as a declassified document may differ materially from the original classified 
 document by reason of deletions necessary to accomplish declassification, this copy does 
 not constitute authority for declassification of classified copies of a similar document which 
 may bear the same title and authors. 
 
 I 
 
 Date of Manuscript: Unknown 
 Document Released: January 17, 1947 
 This document consists of 2 pages. 
 
- 1 - 
 
 MDDC-884 
 
 AN INTEGRATION RADIATION METER FOR BETA AND GAMMA RAYS, 
 SIGMICN, MARK J.0, MODEL 70 
 
 The instrument consists of a 50 cc ionization chamber and an electronic circuit which is 
 so constructed that when the total amount of gamma radiation falling on the chamber reaches 
 any selected value up to 20 mr, an alarm rings, the circuit is reset, and is again ready to 
 operate. 
 
 Each time the circuit is reset a message register is operated so that the total amount of 
 radiation falling on the ionization chamber in any length of time can be measured. 
 
 The circuit as shown in the diagram uses a Victoreen V32 tube in an inverted manner so 
 that the normal plate is the control grid and the normal grid is the plate. When used in 
 this manner the effective grid currents are of the order of 10 _ ^ amperes and do not vary 
 appreciably with effective grid potential. These grid currents are balanced out by an ad- 
 justable uranium rod suitably placed in the ionization chamber. 
 
 The instrument is self-contained with a battery life for continous use of approximately 3 
 months. A cap is provided which may be placed over the ionization chamber to exclude 
 beta particles from entering it. This instrument has been found very useful for determin- 
 ing the integrated amount of radiation present in any locality. Weight about 15 lbs. 
 
MDDC-884 
 
UNIVERSITY OF FLORIDA 
 
 3 1262 08909 7850 
 
 I