SIDE VIEW 



Figure N-7. 



Top, side, and end view of instrument 

 holder assembly. 



N-9 Checkout of the Underwater Camera 

 System. — At the beginning of a survey opera- 

 tion, the camera system should be checked out to 

 be certain that all components are functioning 

 properly. The instruction manual for the camera 

 should be on hand as a reference to supplement 

 the following instructions : 



Step 1. Remove rear end caps from the hous- 

 ings, and remove chassis from cameras, light 

 sources, and battery packs. CAUTION; The 

 end caps and housings for all units must be 

 kept mated or flooding could result. 



Step 2. Remove end caps from housings. In- 

 spect "O" rings and sealing surfaces of front end 

 caps for cuts, scratches, dirt, etc. ; apply a light 

 coating of grease on the "O" rings and the seal- 

 ing surfaces. Replace front end caps, being sure 

 to tighten housing clamps and side straps. Rear 

 end caps must be temporarily replaced with 

 wing nut tightened in order to secure front end 

 caps. 



Step 3. Load film (use dummy film to famil- 

 iarize operator with film loading technique) 

 by threading through the camera in accordance 

 with film path marked in white on the base- 

 board (fig. N-2). 



CAUTION: Do not bend the spring plate of 

 the film gate away from film gate block when 

 inserting film. Press lower edge of film into the 

 slight groove between the top of the block and 

 the spring plate and the film then slides down 

 into position. The bronze guide roller's locate 

 the film vertically. 



Step i. Connect a ground wire between all 

 chassis, and connect all units as shown in the 

 wiring diagram (fig. N-8). 



Step 5. Set the time delay unit in battery 

 pack (Model 280) to zero, and connect the On- 

 Off lead. The system is now activated, and the 

 light source lamp and the data lamp should 

 flash approximately every 15 seconds, and the 



Figure N-S. Wiring diagram for cameras, light 

 sources, and battery packs. 



film in the camera should advance one-half 

 revolution of the film drive sprocket beween 

 flashes. If malfunctions occur, refer to the 

 instruction manual. 



N-10 Preparing Underwater Camera Com- 

 ponents for Installation on Mounting 

 Rack. — Before cameras, light sources, and bat- 

 tei-y i^acks are installed on the mounting rack 

 perform the following steps : 



Step 1. Load the camera with fresh film (for 

 film selection, see fig. N-9) in subdued light in 

 accordance with Step 3, paragraph N-9. Test 

 film spools (supply and take-up) in the clear- 

 ance gage on the camei"a chassis, and replace 

 if faulty. Snap film spools in place, and tape the 

 film leader to the take-up spool. Remove the 

 drive belt from the take-up spool pulley, allow- 

 ing take-up spool to rotate freely and wind sev- 

 eral turns of film on the spool. Replace drive 

 belt, insuring that film is snug. 



Step 2. Fill out a paper data card, using 

 India ink or a ballpoint pen, and secure it in 

 place over the permanent plastic data card. 

 NOTE; Penciled data on permanent card will 

 not photograph satisfactorily. 



Step 3. Wind the clock and set it to the near- 

 est second GMT time. 



Step 4. Check the data lens for cleanliness 

 and open to maximum aperture. 



Step 5. Check the objective lens and window 

 for cleanliness, and for operations deeper than 



N-5 



