Operating instructions

3-4
• If the indications are that the fault is in the CP45, perform the
checks below after you have turned off the power amps to prevent
loud thumps in the theatre.
• With the CP45 still in bypass, check the screw terminals at the
back of the unit where the two power transformers connect, if any
of the screws is loose, re-tighten and check all the other terminal
block screws for tightness.
• Locate the four red LEDs at the front edge of the Cat. No.512
main board, (they indicate the status of the four main power
supply voltages). Switch the CP45 from bypass back to normal
operation, and watch what happens to the LEDs.
• If all four LEDs stay on steady, the power supply section of the
Cat. No.512 is working properly. If any one of them is dim or out,
the Cat. No.512 may be at fault, and, if available you should try
substituting a spare Cat. No.512 or call your service engineer to
correct the problem.
C. WHEN THE THEATRE IS CLOSED
If you can take the time, the following procedures may help you to track
down which part of the CP45 may be the cause of the trouble. If you
have to telephone your service engineer, the information you obtain can
reduce the time required for him to correct the malfunction. Remember
that you can still operate the system in bypass.
If the CP45 is one of several in a multi-screen theatre, temporarily
substituting a board from another CP45 can help confirm your diagnosis.
However, if you borrow a part from another unit, do not change the
positions of any of the preset controls or jumpers and be sure to
replace it in the unit from which it came. Nearly every module in the
CP45 has been adjusted and jumpers have been programmed for its
particular auditorium. Interchanging modules can result in poor sound
or control errors.