Sound Pick-Up System; 7-1: Optical Sound Focusing Procedure A. Description; Alignment; Tools And Equipment - Eiki ESL SERIES Service Manual

322-7:SOUND PICK-UP SYSTEM
7-1 OPTICAL SOUND FOCUSING PROCEDURE
A. Description
Models ESL/SSL-0, 1 are optical sound playback only, models ESL/SSL-2 are both optical
and magnetic playback. The optical pick-up system resembles a small projector within a
projector, consisting of a light source, a lens, an image, and a screen or target.
The light from the exciter lamp is focused through the sound track imaged onto the (target)
solar cell where varied light intensity is converted into a minute electrical voltage change
which is amplified and converted into acoustical variation or sound directly related to the
photographic variations recorded on the film. (Fig. #98)
B. Sound Focus Alignment Procedure
1. Tools and Equipment Required
a. Screw driver set (Iso)
b. Sound lens adjustment tool (Tool No. 320-02T. Fig. #100)
c. SMPTE sound focus test film 7000Hz
d. SMPTE buzz track test film
e. AC VTVM (audio range) and or
f. Oscilloscope
g. 8 ohm 30 watt dummy load resistor
h. External speaker (front cover)
2. Set-up Procedure .
a. Remove the lamp house cover, light shield and lamp.
b. Load a SMPTE test loop.
c. Turn the function control to "MIC" position.
d. Loosen a screw mounting sound lens holder assy, and remove the lens holder assy.
e. Insert the Tool No. 320-02T on the larger barrel of sound lens and tighten a set screw on
the tool. (Fig. #101)
f. Loosen a sound lens lock screw, and mount the sound lens clamped to the tool to
the lens holder assy.
g. Mount the sound lens holder assy to the projector's casting and tighten the mounting
screw. (Fig. #102)
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