SECT. 1] 



REFRACTION AND REFLErTION TECHNIQrEi5 AND PROCEDtTRE 



27 



HYDROPHONE 1 



HYDROPHONE 3 



FATHOMETER OR 

 HYDROPHONE 



AMPLIFIER 



I 



MICROPHONE 



RADIO 

 • TRANSMTR 



CHRONOMETER "' 



PEN 

 rl RECORDER 



SHOOTING SHIP 



HAfflCp- JHF AMPLIFIER 



HIGH 

 PASS 



FILTER 



RECTIFIER 



FROM 

 HYDRO 3 



1. 



RCVR 



AMPLIFIER 

 RECTIFIER h 



CHRONOMETER 



POWER 

 AMPLIFIER 



POWER 

 AMPLIFIER 



RECEIVING SHIP 



PEN 

 RECORDER 



Fig. 5. Block diagram; SIO shooting and recording system. 



AX 58 

 HYDROPHONE 



+ 90 V 



OUTPUT 



« +6 VAT 150 MA 



SHIELD 

 - COMMON 



CALIBRATE 



100 



A X58 



HYDROPHONE 



• +90 V 



* +1.34 V 

 OUTPUT 



SHIELD 



COMMON 



CALIBRATE 



A) SIO PREAMPLIFIER 



B) LGO PREAMPLIFIER 



lOOK 



Ax 58 

 HYDROPHONE 



« +90V 



• OUTPUT 



* +6V AT300MA 

 GROUND 



r— * SHIELD 



COMMON 

 ■• CALIBRATE 



OWHOI PREAMPLIFIER 



Fig. 6. Hydrophone pre-amplifiers. 



