Operating instructions

3-10
D. TROUBLESHOOTING PROCEDURES (cont'd)
Trouble Probable Cause Recommended Action
When a stereo film is projected,
the sound appears to be coming
from the wrong speakers.
The A-chain has become misaligned. Call service engineer.
You can hear pops and thumps
during projector changeover.
If your projector changeover relay power is DC,
a diode should be soldered across the winding
of the relay to prevent noise from the relay
winding from leaking into the audio wiring.
This diode may be missing or defective.
If your projector changeover relay is AC, a
capacitor soldered to the relay coil terminals
may be defective.
Malfunctioning Cat. No. 514 optical
preamplifier card.
If possible, check that the diode is installed
across the relay winding. If you are familiar
with such electronic components, check to see
that it is not blown. If the diode is not present
or if it appears to be blown, install a good
diode. Activate the changeover and use a
multimeter to find the polarity of DC that
appears on the relay coil. Install the diode with
the band end soldered to the terminal that is
positive when measured with the meter.The
diode should be a 1N4004 (1 Amp, 400 V), or a
1N4008 (1 amp, 800 V diode) or equivalent.
Install a .01µF 600V capacitor to the relay coil
terminals.
Call service engineer to correct the
malfunction.
Sound from the front (screen)
channels is leaking into the
surround channel.
The A-chain has become misaligned.
Surround sound delay set improperly.
Surround sound level set too high.
Call service engineer.
Call service engineer.
Call service engineer.