User`s manual

2-12
With CP45 FADER turned up and format 04 selected:
5. Solar cell wiring. Check the shield connections. Cell wiring
should be placed away from mains and other wiring. Cell
wires must not be connected to the frame of the projector.
6. Exciter lamp power supply. Check for ripple on the DC
power supply outputs. Some old exciter lamp power supplies
and emergency supplies provide AC to the lamp. The resulting
hum makes them totally unsuitable for a Dolby film sound
system. Such exciter supplies must be replaced.
7. Projection room lighting/solar cells. Ambient lighting,
especially florescent tubes, can leak into the solar cell area and
cause hum.