User`s manual

2.11
2.6 Connect the Transformers to AC Mains Power
a. With the
NORMAL/BYPASS
switch in the
NORMAL
position, verify that
the
BYPASS
indicator is off and any one of the format switch indicator
LEDs is on.
b. Select each format in turn, using the buttons on the front panel and check
that the associated LED lights. If either format 04 or 05 LEDs do not remain
on when their select buttons are released, then the Cat. No.222 card may be
loose.
c. Set the
NORMAL/BYPASS
switch to the
BYPASS
position. The bypass
indicator on the front panel should blink.
d. Return the
NORMAL/BYPASS
switch back to the
NORMAL
position and
apply power to the other projection room equipment.
2.7 Hum Problems
If you hear undesirable hum from the speakers when you apply power to the CP45 and
other projection room equipment, check the following list for possible causes:
1.
Ground loops
caused by audio signal wiring, especially to power
amplifiers. Be sure to check the booth monitor installation.
2.
Projector power wiring
. All mains wiring should be properly grounded.
3.
Room lighting dimmer controls
(SCR-TYPE).
4.
Power amplifiers
. Disconnect from the CP45 and ground the inputs to
determine if the power amplifiers are causing hum problems.