TM No. 377 

 CONTENTS (continued) 



Page 



Random Biased Model • C-17 



Sinusoidal Unbiased Model • C-20 



Sinusoidal Biased Model C-23 



APPENDIX D : Digital Computer Programs D-l 



Veloc ity Convers ion Program ( VELTIME ) D-l 



Combination Spectrum Program (Program BBELS ) D-l 



Head -to -Tail Vector Plot Program (Program NUWS ) D-ll 



ILLUSTRATIONS 



Following 

 Figure Page 



II-l. Typical Configuration of Electrical Impeller Type 



Current Meters • 19 



II-2 . Schematic Diagram of the Ducted Meter 20 



II-3- First Orthogonally Mounted Ducted Meter System 21 



11-^. Wiring Diagram for Ducted Meter Magnetic Pickup, 



Amplifier, Oscillator Circuit, and Power Supply.... 21A 



II-5- Calibration Curve Showing Impeller Response to Steady 

 Rectilinear Towing 



II-6. Impeller Response to Accelerated and Decelerated 



Towing 23 



II-7- Typical Voltage Pulses Produced by the Magnet-Coil 



Detector 2k 



II -8. Worcester Polytechnical Institute Rotating Boom Sys- 

 tem at Holden, Mass 



II-9- Calibration Curve of Impeller Response to Steady 



Boom Rotat ion 26 



11-10. Orientation of Ducted Meters to Define the Angles 



and 27 



11-11. Orientation of OMDUM II System at End of Boom 28 



11-12. Values of R(+0) and R(-0) for Various Towing Speeds.. 29 



11-13- Strip Chart Record Showing Simultaneous Recording of 



OMDUM II and Accelerometer Outputs 3° 



II-lU. Interpolated Impeller Response Compared to Accel- 

 erometer Response » » • • • 31 



11-15. Small Scale Orthogonally Mounted Ducted Meter System. 31A 



II-16. Closeup of Small Scale OMDUM System Showing Impeller 



Mount ing , . „ . . 32 



11-17- Linearly Mounted Ducted Meter System (Assembled for 



Measurement of Vertical Velocity Component) 33 



ix 



