8
MODIIB STEREO PROCESSOR
strip that screws onto the back of the MODIIB. Make
sure to observe polarity. As you are looking at the
back of the MODIIB, the top left terminal strip is
where the power supply harness attaches. The power
supply wires will exit from the bottom of the terminal
strip. The red wire should go to the terminal marked
MAIN PS (+), the yellow wire to MAIN PS(-), and the
black wire to GND.
The emergency power supply is contained within the
Main Power Supply. There is a white wire with a red
stripe that is part of the power supply harness and it
should be connected to the MODIIB terminal marked
BACKUP (+).
Remember to check all connections before applying
power to the system. A wire that is reversed could be
very destructive to the system.
WIRING HOOKUP INSTRUCTIONS:
EASY HOOKUP:
All connections are made to rear of the MODIIB via
terminal strips. Inputs, Outputs, Power and Control
connections are carefully laid out in groups. Make
sure each group has good separation between low-
level and high-level signals.
SOLAR CELL HOOKUP:
Using two-conductor shielded cable, connect the wire
from the left solar cell (red) to the corresponding LEFT
projector 1 input terminal of the MODIIB. Connect the
wire from the right solar cell (green) to the RIGHT
projector 1 input terminal. The common solar cell lead
(black) should be connected to the NEUTRAL projec-
tor 1 input terminal, and the shield of the cables
should be connected to a GROUND terminal. Be sure
to cut off the shield at the projector end so that a
ground loop is not created. Only the shields on the
MODIIB end of the cable should be grounded. It is
good practice to tape or shrink wrap the end of the
shielded cable at the sound head to prevent any stray
shield wires from grounding out to the sound head
case.
If you have a second projector, repeat the above steps
except hook your solar cell wires to the projector 2
inputs.
DOUBLE CHECK your work to see that the solar cell
leads arrive at the proper terminals. A reversal of
leads will cause very strange results. You may hear
the center channel information through the surround
speakers, the surround through the stage, and the left
channel out of phase with the right. This is a common
error, so verify correct wiring before proceeding.
CHANGEOVER WIRING OF DUAL PROJECTOR
PREAMPS:
Changeover between projectors is done electronically
in the MODIIB. This necessitates that BOTH exciter
lamps be lit at the same time. No exciter light
changeover is provided in the unit. An exciter light
changeover has at least 3 dB more circuit noise than an
electronic changeover and is NOT recommended in
high quality systems.
Projector changeover is accomplished by using only a
single pair of wires and either a manual switch or
relay contacts in the automation system. A relay clo-
sure in the automation equipment will execute a
changeover by grounding the CHNG-OVER terminal.
Run a 2-conductor shielded cable to the “dry” contacts
of the automation projector changeover relay. On the
other end, connect one wire to the CHNG-OVER ter-
minal on the MODIIB. Ground the other wire to the
nearest ground terminal on the MODIIB. Connect the
shield of the wire, on the MODIIB end, to a ground
terminal. Cut off the shield on the automation end.
When the automation relay closes, PROJECTOR TWO
of the MODIIB will be “enabled,” and the first pair of
stereo preamplifiers (PROJ ONE) will be “disabled.”
Releasing the relay will cause the reverse action to
occur. In other words, PROJ ONE is always ON until
the CHNG-OVER terminal is grounded. The CHNG-
OVER terminal must be held low to activate PROJ 2. It
is not a pulse input.
MUSIC INPUT:
The non-sync music inputs for the MODIIB feature a
special music matrix decoder that separates in-phase
and out-of-phase signals on a standard two channel
recording (CD player or tape) and creates four chan-
nels of auditorium music. Connect your stereo music
source to the MUSIC LEFT and MUSIC RIGHT inputs
on the back of the MODIIB.
Occasionally, a theatre may use a monaural sound
player such as a background music cartridge player
that does not have stereo capabilities. A jumper on the
OUTPUT CARD in the MODIIB is moved to the
MONO position for this use. The music source should
then be connected to both LEFT and RIGHT MUSIC
inputs. Music will appear on all stage channel and sur-
round speakers when mono material is feeding the
sound system.
FORMAT SELECT TERMINALS:
A momentary ground contact to one of the FORMAT
SELECT inputs on the rear of the MODIIB will switch
