Dvd Laser Current Measurement; Cd Laser Current Measurement; Measurement Voltage Value - Denon DVD-2900 Service Manual

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4.1. DVD Laser current measurement

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LD(DVD)
+5V-A2
(1) Connect the oscilloscope to +5V-A2 of test point for GND
side and LD(DVD) of test point for signal side.
(2) Playback the title 1 / chapter 1 of the DVD Test Disc.
(3) Measure the voltage between +5V-A2 and LD(DVD), cal-
culate Iop by the formula as shown below.

Measurement Voltage Value

Iop = ---------------------------------------------------------------------------- -
14 (Resistance value)

4.2. CD Laser current measurement

(1) Connect the oscilloscope to +5V-A2 of test point for GND
side and LD(CD) of test point for signal side.
(2) Playback the track 1 of the CD Test Disc.
(3) Measure the voltage between +5V-A2 and LD(CD), calcu-
late Iop by the formula as shown below.
Measurement Voltage Value
Iop = ---------------------------------------------------------------------------- -
11.75 (Resistance value)
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