The last two are not radiac devices, but are included in this sec~ tion for convenience of presentation. A description of each device is given below, All radiation-measuring devices wre calibrated at Nas prior to the Operation. They were recalibrated intermittently at the test site using a Co © source. e 2,1__KAEC ModelM1432 Autozaic-PeordingRadiation=Rat Coast Elec- (PeMeter). The P-Meter was designad and built by the West tronics Laboratory of the Kaiser Aircraft and Electronics Corporation at Palo Alto, California, under contract with and according to epecifin- cations furnisted by Air Force Special waapons Center (AFSC), Seven recorder unit) and one nonairborre component (playback unit). A block complete assemblies were procured. The equipzent consisted of three airborne composcents (probe, power supply, and compressor-amplifier- diagram showing the relationship of theses units constitutes Figure 2.1. The entire airborne assembly was mounted in the nose section of a B-57B, The instruments were operated by the 28-volt aircraft powr Supply. The wire recorder could be Started manually at any tim during aitinn Ai the flight by means of a switch in the pilot's compartment, It could also be started automatically by use of tke intervalometer setting. Once turned on, it continued te record until the recording wire was con- pletely used (about 2 1/2 hours) or until the power was turned off. r =-----------~--. Wire _ 1 Recorder Blocking Oscillator 1 Gamma [1 Scintillation Probe <SPRaao ==Pi Automatic Recorder A/C 28v A/C 28v Bristot Chart Recorder. +150v Time Morker “ON" Control [77] Integrating Circuit au -,000v 28v dc & + 28v . Univibrator Supply a+150v A/C Supply AIRBORNE UNIT <7 Power 4-Stage Amplifier Wire Playback Recorder GROUND PLAYBACK UNIT . Figure 2,1 (P-Meter).» Block diagram of automatic recording radiation rate meter ee ee ee _ The probe was the sensing elezent and consisted of a Scintilon (trade - pans used by National Radiec Company) sphere, DuNont 6292 photo-multiplier tube, and a regulated voltage divider with temperature compensation. This was housed in a 2 1/2-inch diazeter aluminum tube having a wall thickness of 1/16 inch with an added 0,01 inch of tin outside the hemispherical end thet covered the Scintilon, The inside of this hemisphere was coated with sinc sulfide in order to enhance low-energy response so that satisfactory performance was obtained from &) kev up to 1.3 Mev, © LE COPY BEST AVAILAB lu,