NAV^'/EPS REPORT 76^0 



INTRODUCTION 



A soimd- velocity, temperature, and pressure (SVTP) instrument was built 

 during 1958-I96O at the U. S. Naval Ordnance Test Station (NOTS) to satisfy the 

 need for a continuous -reading instrvmient for the concurrent measurement and 

 data transmission of three of the oceanic parameters (see Fig. l). 



The NOTS-SVTP instrument contains three sections, permitting the simultane- 

 ous measurement of velocity of so\ind, temperature, and pressure as the instru- 

 ment is moved through the water. The velocimeter developed by Greenspan and 

 Tschiegg of the National Bureau of Standards (NBS) and slightly modified by 

 NOTS is the velocity of sound section (Ref. l). The temperature section is a 

 thermistor-controlled Wi en-bridge oscillator developed at NOTS (Ref. 2), and 

 the pressure section is the Vibrotron of Borg-Warner Controls, Santa Ana, 

 California. QThe accuracy of measurement for the NOTS-SVTP instrument is ve- 

 locity of sound 0.3 m/sec, temperature 0.02°C, and pressure ifo in selected 

 ranges . The basic design of the instrument will permit its use in all ocean 

 depths . 



FIG. 1. NOTS-SVTP Instrument. 



