Polaroid SX70 manual Camera/Shutter Isolation, Flex circuit terminal locations

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Figure 3-18 Flex circuit terminal locations

1. Camera/Shutter Isolation

To expedite the repair procedure, it is essential that the malfunction be isolated to either the camera back or the shutter as early as possible in the troubleshooting procedure. The sequence should not be considered inflexible, however.

a. Disassemble the camera to the point where the terminals on the flex circuit are accessible (Figure 3-17).

b. Tack solder a 1000 ohm, 1/2 watt resistor across the VCC and NPN terminals as shown. (This procedure does not apply to mid-cycle shutdown. Refer to the Failure Analysis Charts.)

NOTE : One 10 pad flex circuits, these are the TP6 and TP30 terminals. One 8 pad circuits, these are TP4 and TP21 terminals. One 7 pad flex circuits, where the PNP pad is eliminated, the NPN terminal is located directly adjacent to the VCC terminal. Refer to the inserts in Figure 3-17 to locate the proper terminals.

c. Close S6 and S7 and apply power :

(1)If the camera cycles, the motor and MCC are OK and the shutter is defective.

(2)If the camera fails to cycle, check the motor and MCC by continuing below.

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Contents Page Page Description General DescriptionCamera Operation Opening the CameraLoading the Film pack Starting the Automatic MechanismSetting the exposure counter Viewing and focusingViewing and shooting Completing the film pack Exposures using flashDeveloping the print Shutter Description Ambient Light Mode Closing the camera11 a Location & Arrangement of internal parts Shutter Description Flash Mode Page 14 S5 being opened by the recock ram Gear train Page Lens Power SourceIntroduction Viewing and Exposing SystemFresnel Figures 2-3 a and 2-3 B Viewfinder optics exposingFresnel screen Flare baffle ViewfinderMirrors Camera Elctronics 1. GeneralSwitch functions SX-70 Switch locationsS3 Being opened by recock ram S4 Switch operating configurations Switch Function Table Function SequencePage Flash Timing Sequence Chart Shutter Mechanical Details Figure Shutter, exploded viewA Solenoid S2 operation Film Processing Components Sequence of OperationsPage Max III Troubleshooting Introduction Initial TestsSX-70 Cmaera Repair Inspection Procedure Power supply and pack simulator Figure Test Equipment OperationCollimator Figure Location of new collimator targetDisengaging the idler gear Comprehensive Testers -6 Comprehensive testerModel B Camera tester Model B Camera Tester Comparalumen Light Levels Table Light Leak Tester FigureFlash Simulator Board Figure Light leak test systemManual Function Tester Figure 10 Manual camera testerManual Function Test Sequence Optical System Exit Pupil Test Entrance Pupil Test 13 Aligning the exit pupil gageFresnel Quality Check USE of Analysis ChartsConcave Mirror Distortion Check Collimation16 Fresnel standards chart Camera/Shutter Isolation 18 Flex circuit terminal locationsCamera Analysis Charts 19 Test points on SX-70 shuttersPage Installation Front COVER/SPREAD Roll AssemblyRemoval Repairs / Adjsutments Loose Front Covers Front cover hinge studsBending the stop latch Top Spread Roll Looseness Interference Between Front and Bottom CoversReplacing the Light Shield Cam Mirror Cover / Boot Assembly Front cover light shield camBoot retaining screws