Service Manual

4.2.4.1 Failure of the CdS unit to provide normal resistance.
Undertake continuity test according to procedure outlined in 4.2.3.1. The resistance
reading in this case should also correspond to that given in the same paragraph. If the
resistance is found to be excessive, remove one CdS cell at a time and check their
resistance individually. The resistance reading in this case should be within the allowable
limit specified in Fig. 2.3.1.
4.2.4.3 Shortcircuiting of the BALANCING resistor (VR-1)
Make through check according to procedure outlined in 4.2.3.2.
4.2.5 Adjustment of the exposure readout circuit.
Adjustment of the exposure readout circuit consists of either one of the following two
methods:
One method consists of loosening the two screws on top of the slide resistor assembly
and turning to offset resistor ring to alter its position in relation with the brush. This
method (providing a balanced shifting of the offset resistor characteristics) enables
precise regulation of the 'light turn-off point' without altering the 'light turn-off range'.
The other consists of adjustment of the 30K semi-fixed resistor incorporated in the
amplifier unit. This provides effective regulation of the 'light turn-off point' of the
"OVER" indicator lamp.
4.2.5.1 Improper adjustment of the 'light turn-off' position.
1. The 'light turn-off' position generally tends to shift toward a direction providing
under-exposure at all light levels.
This malfunction is caused when the resistance of the offset resistor (VR-1) rises to a
level beyond the standard reading. To repair, turn the offset resistor ring in a left motion
to effect a balanced shifting of the resistor characteristics.
2. The 'light turn-off' position generally tends to shift toward a direction providing over-
exposure at all light levels.
This malfunction is caused when the resistance of the BALANCING resistor (VR-1)
declines below the standard level. To make adjustment, turn the offset resistor ring in a
right motion.