Kenwood DM-3090 Service Manual

Figure 23-1 Optical Pickup Grating Deviation
Measuring Method
Mechanism Adjustment
1. Optical pickup grating inspecting method
After the automatic adjustment is performed in the AUTO
mode (test mode) with the aid of high refection MD disc
("COMPLATE" is displayed), the Lissajous's waveform (x-y) is
adjusted.
1. Slightly loosen the 3 screws of spindle moto, and maken an
adjustment, observing the Lissajous's waveform.
2. After adjustment tighten the screw in arder of 1 , 2 , 3 .
OSILLOSCOPE
GND CH1 CH2
X Y
42 pin of IC 1101
GND (TP1131)
26 pin of IC 1101
EOUT (TP1133)
25 pin of IC 1101
FOUT (TP1132)
100K
470p
470p
a
b
LISSAJOUS'S WAVEFORM
Less thana:b = 3:1
100K
Figure 23-2
1
2
3
1
2
3
adjusting
hole
Spindle motor
Check the Lissajou's waveform,
shifting the mounting position with
a screwdriver (to be fitted into the
disc motor adjusting hole).
Spindle Motor
Adjusting hole
2. Jitter adjustment and checking method
Figure 23-3 Jitter connection diagram
jitter Meter
1pin of IC 1201 (TP1274)
EFMMON
88 pin of IC 1201 (TP1275)
GND
After performing automatic adjustment in AUTO mode of
TEST mode using the low reflection MD disc, check this jitter
in pit continuous playback and groove continuous playback
mode.
Figure 23-4
5P extension flat cable
2P extension connector
CNP1601(Bottom side)
CNP1602
CNP1252
CNP1603
CNP1604(Bottom side)
CNP1101
MD Main PWB
6P-2P extension connector
28Pextension flat cable
Extension PWB for service
Fit the extension PWB for service to the mechanism
From Optical
Pickup Unit
From Magnetic Head
From
motor
From mecha-
nism switch
PWB
DM-3090
30
ADJUSTMENT
DM-3090(K) COVER 97.11.29 0:19 AM y[W 25

Kenwood DM-3090 Specifications

Digital Audio Performance

frequency response (playback mode)	8 Hz ~ 20 kHz, ± 1 dB
signal to noise ratio (playback mode)	More than 100 dB
wow & flutter	Less than unmeasurable limit

Analog Specifications

analog input sensitivity / input impedance	0.5V / 22 kΩ or more
analog output level/output impedance	2.0 V / Less than 2 kΩ
headphone output	15 mW/32 Ω load

Digital Input/Output

digital input coaxial	0.5 Vp-p / 75 Ω
digital input optical	- 15 dBm ~ - 21 dBm
digital output optical	- 15 dBm ~ - 21 dBm

General Specifications

power consumption	17 W
dimensions width	440 mm (17 - 5 / 16”)
dimensions height	94 mm (3 - 11 / 16”)
dimensions depth	300 mm (11 - 13 / 16”)

Weight

weight	3.55 kg (7.9 lb)