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APPENDIX 2 

 INSTRUCTIONS 

 A. RECORDER SYSTEM 



1 . CAUTION 



AC-DC amplifiers are used in this system. Therefore, when the ampli- 

 fier is mounted, one side of the power line is automatically connected to the 

 case. It is necessary to be absolutely sure that the case is at ground poten- 

 tial before making the external ground connection. 



2 . Power Supply 



Power input connection is at rear of case; use 110- volt 60-cycle 

 alternating current. 



3 . Circuit Diagrams 



See Figures 8 through 10. 



4. Operation 



Install the recorder and connect it properly to the power source and 

 to the transducers (Note the CAUTION, paragraph 1 preceding). Turn the instru- 

 ment power on, switch all amplifiers on, and permit the units to warm up for 

 about 15 minutes. The chart drive motor should be in the off position. 



To adjust the zero position of the pens proceed as follows. Operate 

 the amplifier "CAL-OPF" switch to the "CAL" position; this shorts out the sec- 

 ondary of the transducer LVDT and changes the circuit from a null-balance to 

 a null-seeking system. Adjust the zeros of the several pens by means of the 

 zero adjustment screws, see Figure 4. Throw the amplifier switch to "Off." 

 Now adjust the sensitivities to the required values by means of the "Range 

 Adjustment" screw. The amplifier gain control may be utilized to reduce hunt- 

 ing; the gain setting does not affect the over-all sensitivity of the recorder. 



To record automatically (cycling operation), the "CONTIN-TIMED" 

 switch must be in the "TIMED" position and the "CHART DRIVE, 0N-0FF" switch in 

 the "ON" position. If it is desired to record for a definite interval of time 

 between 5 and 113 minutes, switches are left in the same positions as before, 

 and the "MANUAL SET TIMER" is rotated clockwise to the desired number of min- 

 utes; at the end of this recording interval the recorder will automatically go 

 back to the cycling operation. If continuous recording is required, the 

 "CONTIN-TIMED" switch is thrown to the "CONTIN" portion. 



