The battery box is a separate module from the ion chamber assembly module and was located in the end of the tubular aluminum bousing It contained three Bé-1318/U and one farthest from the control panel, 1328/0 batteries, for 200 hours, These were sufficient to furnish continuous operation 2.2.3 Sigmatron Radiation Integrating Dosimeter. The Signatron was built by the Research Directorate of AFSW, Kirtland Air Force Base (KaFB), and was based on a similar design used by los Alams Scientific Laboratory (LASL) for a much-lower-range instrument, called the "Integron." Eighteen of these units were built, The ion chamber which was used was designed and built by NRDL +o meet specifications prepared by AFSWC. The information furnished by the instrument is total gana dosage, with two ranges (25 r and 100 r full scale) available by chang- ing an internal connection, Two Sigmatrons were used in each eirplane, mounted just behind the pilot, with a remote meter for each. One meter was in the photopanel and the other was in the pilot's compartment. The first prototype of this instrument tested at NBS integrated total dosage with an accuracy of 2 20 percent at energies higher than about 125 kev. At & kev the loss in response was only about 25 percent, independent of rate up to 2,000 r/hbr. Accuracy was A block diagram of the Sigmatron is shown in Figure 2.3. The instrument opsrated as follows: The ion chamber had a sensitivity of 1.1 Control Zero - Bucking de Ammeter Panel Current indicator ~~ 7777 [pues pee -—1 de Amplifier | - poo Signal Current G Radiation ann. lon Chamber \ | po—-lon Chamber Assembly Module 1 LL.-li Jo 7 errercree ——s i) ! Batteries | LoJ3-Ba13i87u j7 Battery Container Module | 1 \ ! 1 \ | 1 j PE BAIZ28/4F } Battery I 1 Temperature --*— 28v de A/C Supply Regulotor | ! Lee d Figure 2.2 Elock diagram of Bioscel radiation-rate meter, 16 LE COP®vd