6 . Edin Amplifier Model 8105 - is a stable high gain D . C . 

 amplifier with means for attenuating the signal to provide 

 the desired size recording on the oscillograph. 



7. Edin Oscillograph Model 8062 - is a direct writing two 

 channel oscillograph, with three paper speeds, 5, 25 and 

 125 mm/sec. A paper speed of 25 mm/sec. was used for 

 most of this survey. A solenoid operated events marker 

 was added to provide the common timing and synchronizing 

 pulse. 



8. Heathkit Oscillator - provides the calibration signal. 



9. Ballantine Vacuum Tube Voltmeter is used to monitor 

 the calibration signal. 



Frequency checks were accomplished by the use of constant 

 paper speed on the oscillograph. In mostx;ases a speed of 25 mm per 

 second was used. On occasion however, a paper speed of 125 mm per 

 second was used. 



The pickups were installed on tri -axial brackets which were 

 clamped to the main thrust bearing foundation and to an angle welded 

 to the deck over the main transverse member at the aft -perpendicular 

 in the steering engine room. Figures 5 and 6 show the pickup clusters, 

 The instrumentation was installed in the workshop just forward of the 

 steering engine room. Figure 7 shows the instrumentation arrange- 

 ment. 



39 



