i.ili'UOARD 

 PaJER 

 SUPPLY 



D. C. POWhR 



|110V,400HZ 

 I INVERTER 



TPTPT 



SHIPBOARD CONTROL 

 SYSTEM 



"1 



L. 



rr3_i 



L.-ZJ 



_PJUlAAA._ J 



LASER 

 POWER 

 SUPPLY 



V 



HIGH 



VOLTAGE 



PO«ER 



SUPPLY 



DISS. I 1 BOXCAR | -S- 



P>I 1 h-E- 



PM 2 \-^ 



m 3 |-€E- 



Fig. 4. Block diagram of electronic syste 



Water samples were obtained with a marine sampling unit attached above the 

 instrument. Sampler can be seen in Fig. 3. A conventional messenger unit is 

 used to operate the sampler during the operating period. 



PROCEDURES 



The instrument outputs are 1-^, Ip, and the laser monitor. The constants in the 

 photomultiplier and dissector equations are obtained by calibration. For the 

 dissector the signal is read with the instrument in air. A special calibrating 

 rig is used for the photomultiplier calibration. A front-surface mirror 

 deflects the beam into the photomultiplier window. A calibrated neutral dens- 

 ity filter reduces the level 5 orders of magnitude. This calibration gives the 

 product 



%%% • 



The factor 2]^ depends on the photomultiplier geometry and the measured attenu- 

 ation length which can be determined from the dissector output. 



The operating procedure for the instrument at sea involves calibration, surface 

 deployment, washing, deployment to depth, operation and retrieval. The on-deck 

 calibration involves recording the dissector output with the laser on. This 



VII-37 



