Dolby Laboratories CP650, Руководство по установке

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Dolby
®
Model CP650 Installation Manual Digital Soundheads
6-3
Figure 6–2 Digital Video Oscilloscope Image—Focus Adjustment
6.4 LED Brightness Confirmation and Adjustment
The optimum peak video signal voltage (unobstructed light through the perf hole) is
4 V , measured from the 0 V reference baseline to the upper trace . If necessary,
adjust the Cat. No. 701 power supply output to achieve the correct video voltage. See
Figure 6-3 for adjustment location (VR1). The back cover of the digital soundhead
must be removed to gain access to the output adjustment.
Output Adjust
(VR1)
Figure 6–3 Cat. No. 701 LED Brightness Adjustment
6.4.1 Inboard Digital Readers
There are several varieties of basement readers, some use lamps, and some use LEDs
as the illumination source. Refer to the instructions for the built-in reader for details
on adjusting lamp/LED current. In any case, the proper video level is 4 V. If the top
of the video waveform is not reasonably flat (±1 division), check for dirt, dust, or
other obstruction to the light path, and clean.