ameter of 3.15 inches and height of l inch. An aluminized ccating was applied to the outside surface (see Figure C.2). The cylinder vas held ; the pressure element, two accelerometer elezents could be installed in the gage on post provided for them. Dry batteries supplied ccwer to {the initiation circuit and motor, the instrument being completely self- ; fontained, \ La] The gage was fitted with a rubber sealing gasket and encased in ‘ae hort section of 5-inch pipe. A pipe cap welded to the bot<om of oy i : BV. eet = - _ ry | NN ; FWO. (OFF AY “ ~ re,tay . assembly along its shaft. The drum rotated at 6 rpm and advazzed 0.025 inches per turn. The standard pressure elezents were used in the gage. The recording drum moved past the pressure element stylus poinz at a speed of approximately 1 in./sec. and a helical base line was zenerated. Figure C.6 shows a view of the gage without its case. In addizicn to REV. ~ _ (for to T SIGMA RELAY 100K JL iP40 PHOTOTUSE Figure B.1 MOTOR x hea sentry, pers avitrecrte “henteerenaneran sate renewal in a drum-like assembly mounted on a threaded shaft. Througs 2 set of gears, a 6 volt D.C. chronometrally governed motor drove the ér= ADVANCE RELAY 7 [es E Drum gude|schenatic diagram. the case sealed it and allowed the gage t e screwed onto @ 35-inch pipe if that method of installation was desired. A steel moatmting-~ ring was provided for installing the gage ih the regular 6-irncn pipe ia nount. B.3.2 Initiation pond LL. The drum gage was started by a photoelectric’ circuit {see Figure B.1 for Drum Gage Schematic Diagram). This circuit wap iemed so that the incident light from the detonation would permit e current to relay and power wag supplied to the constant-speed motor. ‘The 1P40 flow through the coll of the very sensitive Sigma rel 9° 32 its contacts to close. The Sigma contacts closing energi ledth e a3vance 59 a

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