Simplex APOGEE, Instruction Manual And Parts List

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The duty cycle (time ON) of the L.E.D. is the same as the projector motor and should parallel that of the
xenon bulb; the lamphouse elapsed hour meter should indicate approximate L.E.D. hours. L.E.D. manufactur-
ers have noted a 10-20% drop in light output after prolonged operation. If a sound signal loss cannot be
corrected by fader gain, it may be necessary to replace the L.E.D. head.
WIRING
Install the LS-40 L.E.D. Power Supply to the projection console, pedestal, or to a rack adjacent to the
soundhead. Set the slide switch for the desired AC power, and connect to AC source. Route the power leads to the
soundhead-mounted L.E.D. illuminator assembly using 18 gauge wires for short runs; 16 gauge wires for exces-
sively long runs. Other installer connections are made to the clearly-marked terminals on the back of the unit.
The L.E.D.’s are bipolar; the power supply cannot damage an L.E.D. through reversed polarity. It is safe
to try reversing the polarity if you have power but no light. Accidental connection of the L.E.D. to the pre-
amp power terminals will damage the L.E.D. The pre-amp power to the analog reader (Signal Pick-Up) is 12
V.DC+, ground, and 12 V.DC-. The ground must be connected at both ends as it is circuit reference zero volts.
It is recommended to use (2) shielded two-conductor cables to connect the solar cell outputs, but
use of a three-conductor, single-shield cable is permitted. If using three-conductor cable, strap the two “LO”
terminals together. Since very little current is required, 22 gauge wire is adequate. DO NOT interconnect
input and output grounds.
Digital readers utilize a second LS-40 Power Supply. Use 16 or 18 gauge hookup wire between the
L.E.D. and the LS-40 power supply, depending on the length of the run. Pre-terminated digital output cables
(51-98272) are supplied, and should be connected to the processor as instructed in the Dolby manual.
ANALOG ALIGNMENT
Energize the LS-40 and check for 450 mA output to the analog (inner) L.E.D. Connect test equipment to
solar cell output terminals. Turn the sound processor’s level and high frequency adjustment to minimum
settings.
Loosen, but do not remove, the socket head screw clamping the inner L.E.D. head to its mounting post and
bracket. Loosening this screw permits moving the L.E.D. head up and down, and on the horizontal plane (in
and out). Position the L.E.D. head to visually locate the light source directly opposite the lens opening of the
analog signal pickup assembly.
Run a loop of level set (“Dolby Tone”) film and observe the output of the LEFT and RIGHT channels.
When the highest output is seen, move the L.E.D. head horizontally (in and out) inside the impedance drum.
DO NOT permit the L.E.D. head to touch the inside of the impedance drum. Observe the output and secure the
L.E.D. head when the highest output is achieved. Refer also to the sound processor manual.
Run a “Buzz Track” (SMPTE No. 35-BT) loop and check for correct sound track alignment. It is recom-
mended to splice together a loop of half “Buzz Track” film and half “Left/Right Alignment” (Dolby Cat. No. 97)
test film. This permits centering the soundtrack and checking for cross-talk simultaneously. If correction is
required, loosen or tighten the 1/4-20 locknut to move the spring-loaded pickup assembly horizontally.
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