Simplex APOGEE, Инструкция и список запасных частей

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To minimize microphonics, the L.E.D. must be very accurately aligned.
• With the power amplifiers OFF, turn the processor and monitor gains FULL UP. Select a film format and
the correct projector on the processor. Run the projector with no film. Fine-adjust the L.E.D. mount
rotation to a point where the sound of the projector running is not heard through the sound system. The
optimal adjustment will be found between two positions where the projector vibration can be heard quite
clearly. Run Dolby Tone again to give the system a final adjustment. The final result will be projector
noise that is below the noise floor of the processor.
• Optionally, connect an AC millivolt meter to one of the pre-amp test points. Rotate the L.E.D. mount to
achieve highest output to three decimal places on the AC millivolt meter. Careful peaking will achieve
the same result.
Digital Reader Alignment
• Thread and run a reel of Dolby-encoded film.
• Connect a dual-trace oscilloscope to the Dolby Digital Processor per the following instructions.
• Refer to the oscilloscope traces “A” - “D” on the following page in reference to the following instructions:
Figure B is in optimal alignment.
• In Figure A, the top of the sprocket hole has (12) large saw teeth. The differential between the high and
low points is 1/3 volt.
• Figure B shows more saw teeth with less differential. This is obtained by fine-adjusting the rotation of the
L.E.D. holder.
• In Figure C, the sprocket hole is falling off on the left, indicating uneven light. This is improved by
moving the L.E.D. holder laterally until a flatter trace is obtained.
• In Figure D, the CCD board is misaligned laterally. Dimension X2 is smaller than X1. This can be
improved by loosening the moving the board until the X1 and X2 dimensions look like Figure B. The correct
alignment is offset to the left by one minor division. That is, the sprocket hole will be 1/5 of a square off-
center toward the left “goal post”on the ‘scope screen.
Instructions for Alignment of Readers for Dolby Digital
1. Connect a dual-trace oscilloscope to test points on Video Acquisition Card (Cat. No. 605 or 670). Oscillo-
scope should be 20 MHz. minimum.
a) Connect Channel 1 to Video test point; connect this probe ground only to Gnd. test point.
b) Connect Channel 2 to Clamp test point.
c) Set both channels Volt/Div. controls to 1 volt/div. Set vernier to calibrate. Ensure that probes are
not at X10.
d) Set horizontal sweep rate to 2 usec/div.
e) Set trigger to channel 2 and positive polarity, adjust trigger level, and lock on signal.
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