Teac VRDS-20 User manual

TEAC,
SERVICE MANUAL
VRDS-20
Compact Disc Player
COMPACT
DIGNAL AUDIO
Effective : March, 1993 574064200

VRDS-20
1 SAFETY INFORMATION
[ SAFETY INFORMATION
This product has been designed and manufactured according to FDA regulations “title 21, CFR, chapter 1, subchapter J, based on the Radiation
Control
for
Health
and
Safety
Act
of
1968”,
and
is
classified
as
class
1
laser
product.
There
is
not
hazardous
invisible
laser
radiation
during
operation
because invisible laser radiation emitted inside of this product is completely confined in the protective housings.
The label required in this regulation is shown (1).
CAUTION
2
@
If
you
remove
the
above-mentioned
housings
under
the
operating
state
of
the
product,
there
is
a
possibility
of
human
access
to
the
invisible
laser
radiation
emitted
from
the
optical
pickup.
Pay
careful
attention,
not
to
let
the
invisible
laser
beam
enter
into
your
eyes.
@
If
you
find
a troubled
state
of
the
laser
diode,
change
to
the
specified
new
optical
pickup.
@
If
you
find
a troubled
state
of
safety
interlock
parts,
change
to
the
same
type
parts
described
in
parts
list.
® CERTIFICATION
THIS PRODUCT COMPLIES WITH DHHS
RULES 21 CFR SUBCHAPTER J APPLI-
CABLE AT DATE OF MANUFACTURE.
TEAC CORPORATION
3-7-3 NAKA-CHO MUSASHINO-SHI TOKYO, JAPAN
MANUFACTURED uF
Optical pickup: Type : KSS-151A
Manufacturer : SONY Corporation
Laser output : Less than 0.2 mW on the objective lens
Wavelength : 760-800nm
* CAUTION * ACHTUNG * OBSERVERA * ADVARSEL
® THIS LABEL 1S ATTACHED TO THE PLACE AS ILLUSTRATED TO INFORM THAT THE
+
Hawise
LASER
mADAtION
WHEN
OPEN
AND
APPARATUS
CONTAINS
A
LASER
COMPONENT.
INTERLOCKS DEFEATED AVOID EXPOSURE TO BEAM
UNSICHTBARE LASERSTRAMLUNG TOITT AUS,
NN CGF NET UND WEN!
Stone ter SvEWIWE GELUNG. Uae ROALCKT 1st
NICHT DEM STRAHL AUSSCTZEN'
AR
OFPSAD
OLN
SPAR
AR
URROOPAD
(4)
DIESE
AUFKLEBEMARKE
IST
AN
DEM
IN
DER
ABBILDUNG GEZEIGTEN
ORT
STRALEN AR FARLIG
ANGEBRACHT UM DARAUF HINZUWEISEN, DASS IM INNERN DES GERATS
EINE LASER-KOMPONENTE BEFINDET. '
‘o PASKRIFTEN SITTER PA APPARATEN SOM VISAS SOM UPPMANING OM ATT
APPARATEN OMFATTAR EN INBYGGD LASERKOMPONENT.
AQVARSEL,
USYNLIG LASERSTRALING VED ABMING, WA
six TUDE AP FUNK TION
Geuin O0oe FTELSE FON SHAKING
NARDIVIS! -SUOIARDTSEO ASA AUNT LATS BSA
FIIQOIN JOKA LAMETTAA (AK YMATONTA)
SUMALLE VAARALUISTA CASERSATERYA
ADVARSEL USYMLIG LASERBESTRALING NAR DENNE DELEN ER
|SSPERREN ER UTKOBLET
CRMGA UISETTECSE FO STRIALING
‘o DETTE M/ERKAT ER ANBRAGT SOM VIST | ILLUSTRATIONEN FOR AT ADVARE
BRUGEREN OM AT APPARATET INDEHOLDER EN LASERKOMPONENT.
@® 2) DETTE M/ERKAT ER SOM VIST PA ILLUSTRATIONEN ANBRAGT PA INDERSIDEN AF
TOPD/EKSLET FOR AT ADVARE BRUGEREN OM AT YDERLIGERE FREMTRAENGEN
VIL VERE FORBUNDET MED FARE FOR AT UDS/ETTE SIG FOR LASERSTRALING.
ADVARSEL — BETJENING AF ANDRE KONTROLLER OG REGULATORER ELLER
BENYTTELSE AF ANDRE FREMGANGSMADER END BESKREVET HERI ER FOR- id
BUNDET MED FARE FOR UDSAETTELSE FOR LASERSTRALING.
VARNIG: APPARATEN INNEHALLER LASER KOMPONENT MED
STRALNING OVERSTIGANDE KLASS 1
“ADVARSEL: USYNLIG LASERSTRALING VED ABNING NAR
SIKKERHEDSAFBRYDERE ER UDE AF FUNKTION. UNDGA
UDSAETTELSE FOR STRALING”
"VAROITUS! SUQJAKOTELOA EI SAA AVATA. LAITE SISALTAA
LASERDIODIN. JOKA LAHETTAA (NAKYMATONTA) SILMILLE
VAARALLISTA LASERSATEILYA’.
ADVARSEL: USYNLIG LASERBESTRALING NAR DENNE
DELEN ER APEN OG SIKKERHETSSPERREN ER UTKOBLET
UNNGA UTSETTELSE FOR STRALING.
CLASS 1 LASER PRODUCT
LUOKAN 1 LASERLAITE
KLASS 1 LASE?APPARAT

AUDIO
Number of Channels
2 SPECIFICATIONS
ft Ee
2
Frequency Response 1 — 20,000Hz + 0.3dB (RCA)
Signal to Noise Ratio
Dynamic Range
Harmonic Distortion
Wow and Flutter
Channel Separation
Output Analog
Digital
D/A Converter
Digital Filter
Analog Filter
PICK UP
Type
Objective Lens
Laser Type
Wave Length
SIGNAL FORMAT
Sampling Frequency
Quantization Bit
Channel Bit Rate
20 — 20,000Hz + 0.5dB (XLR)
Better than 110dB (1kHz)
Better than 99dB (1kHz)
0.0013 % (1kHz)
Unmeasurable (Quartz accuracy)
Better than 110dB (1kHz)
2.2Vrms (RCA)
2.3Vrms (XLR)
0.5Vp-p/75 Q (Coaxial)
-15dBm —~21dBm (Optical ; TOS)
-12.5dBm —-15dBm (Optical ; ST)
Bitstream Conversion
8-times oversampling 20-bit digital
filter
3rd order Butterworth filter
Optical 3-Beam laser pickup
2-dimensional parallel drive
GaAlAs type semiconductor laser
780nm
44.1 kHz
16-bit linear/ channel
4.3218Mb/sec
Channel Modulation Code
Error Correction
GENERAL
Power Requirements
Power Consumption
EFM (Eight to Fourteen Modulation)
CIRC (Cross Interleave Reed
Solomon Code)
120/230V AC, 50-60Hz (U.S.A./
Canada/ General Export Model)
230V AC, 50Hz (Europe Model!)
240V AC, 50Hz (U.K. Model)
22 watts
Dimensions (W x H x D)
Weight (net)
500 x 146 x 331mm
(19-11/16" x 5-3/4" x 13-1/16" )
13.8kg (30-7/16 Ibs)
Standard Accessories Wireless Remote Control Unit
(RC-481 ; for Gold finish version
/RC-495; for Black finish version),
Battery (SUM-3, “AA”, “R6”" type)
x 2, Lock Plate, Foot Base x 4
@
improvements
may
result
in
specification
or
feature
changes
without
notice.
(A-F 4 7)
A-Frx AF VRE
Bpestoaed
SN EE
FAFRVIVYY
ARES
a i hoe
Fe VRIVEIND-Yay
FFOTHA
FUNDA
DSA DYIN-F-
FUINDANG—
PFFOAI4N9—
(Ex IP uv)
AX
WL VY ARHAX
bint]
RE
25 74—Vvy b)
AER
Btitty hx
ini& LY — b
RRAX
L5—asTIEAHX
(AX)
Ek
BRED
WME TE
28
Raa
VRDS-20
2F ev VAIL
1~20,000Hz + 0.3dB (RCA)
20~20,000Hz + 0.5dB (XLR)
110dB ELE CEIAJ)
Q9dB LIF (EIAJ)
0.0013 %ELF CEIAJ)
AVE RR RB Okan ita)
110dBLiE (EIAJ)
2.2Vrms (RCA)
2.3Vrms (XLR)
0.5Vp-p/75 Q (COAXIAL)
-~ 15~- 21dBm (OPTICAL TOS)
— 12.5~- 15dBm (OPTICAL ST)
Ey bARU-L
BEA-N-TUPUYT
20Ey KF YIN D 4a
SRNI-D-AD4NW9—
HL ASB, HPKBE-L
2 ARTETA
BRL Yt
780nm
44.1kHz
Ey hk UDP/F eR
4.3218Mb/sec
EFM
CIRC
100V AC 50-60Hz
18W
500 x 146 x 331mm (W x Hx D)
13.8kg
@e71VLAVEAY RC-481
@ 8 Bit B3, SUM-3) x2
@nx77L-+t
@7ybkX-A2x4
ORAS
* CBRE KUSH, DESOTO PES BETS CLM) ET.

VRDS-20
3 CASE AND FRONT PANEL REMOVAL
HEB an OLA
number-o emble in
Disass
BSMRCHLT ¢ EA

VRDS-20 _
4 ADJUSTMENT AND CHECKS
aa ae t HERS
1. Replacement of the pickup assembly
@ Before removing the pickup assembly be sure to solder
-bridge where indicated in the inset (Fig. 4-1) to prevent
the laser diode from being electrostatically damaged.
After replacing the pickup assembly, be sure to unsolder
the antistatic bridge. Or else the laser diode.does not
function.
@ Before servicing the pickup assembly be sure to prevent
electrostatic-inducer destruction by grounding not only
test equipment in use but also yourself as shown in
Fig. 4-2,
* Electrostatic charge drastically shortens the operating
life of the laser diode or possibly results in its
destruction.
@During the transportation, mounting and dismounting
of the assembly, support with your fingers at points
A and B as shown in Fig. 4-3. Be particularly careful
not to touch the actuator, photosensor and LD plate
and do not apply force to them.
@Don't touch the plated portion of the flat cable end
directly with fingers.
@Use care not to break the flat cable.
@Soldering must be done quickly at less than 30W, 320°C.
@Don't disassemble the pickup ass’y.
@Don't apply shock to the pickup ass’y.
@Don't place the assembly in a place subject to excessive
dust, heat or moisture.
2. Objective
@lLaser beams are similar to infrared rays. Don’t look at
the beams directly and keep your eyes at least 30cm
away from them.
@Don't touch the objective with fingers.
@If objective becomes dirty, playback will deteriorate.
To clean the objective, moisten a good cleaning tissue,
such as made by KODAK, in isopropy! alcohol and wipe
the objective gently. Wipe off and excess fluid with a
dry cleaning tissue.
Earth ring
(Lead wire)
Pick-up case
Chassis (GND)
Earth
Fig. 4-2
1b y97 17 ASSY OZR
@eyr IT vTSASSY FEAF ERI. VAP AA PORS
DERDIL ORD, BRS (Fig. 4-1) 24M TY y YLT
DOVBELTCR AW. Ek. MOU SBR OM hhh
ICHAT y VEALTCR
MID) y VALHEEE CML AF-S 4a Fide lL EE
Ao
@LYVITITASSY EMYORIBSU. MER CMB
F-AEMAZEHI. MAT -AZEAOW, BBR TOME
LT< HAW, (Fig. 4-2)
KL-F-VAA-— KA, MBAWMDS & HOB AEF
LED, EVIE LET OCLHERBLTC KS.
ORO, ROAL, HEMUORIL, Fig. 4-3SD AME BM
CHATS HEY, B77 Fazt—-F7—-, HREM, LDF
V—bmRid, FRANEOWEMAKY LIEWEC KEW
OVI VhTA-FNVEBO X y HRS} UV EL BEE HART TL US ¢
TEKW
OPT IKTH-TFHNisNET OO CHIERE L THER LTS
TES WG
@ HAF IL380W, 320°CEL FHIBHIL. SIS < MEBL TC KS
Wo
@EYVIT YTASSY AAKORMBS KODE EV LEWECK
Sv,
@EYITYTASSY IBF + HBRUMABEK KAW.
@2ti -KIVREORET Zim, Rik SMO LHY T
CHEWS
Resistor
IMQ~10MQ LO Plate
Photosensor
Fig. 4-3
2. dL vy Z(ICDWT
OL —F-HILLATAROAAHMILRHTT. HORBEOA, A
AVY APS 30cm LEBEL TK KEV,
@VVAIILFEMNEUES CHEW,
@LVVALIENANE ¢ &CHEREFIAVR FL EG OC, ROLZK
fat# UTC TER,
VY AIY-aYVIR—-S— (KODAK HH EY) KL fv o
E-IWPVIA-W (LP.A) BRL CHS LL RAR Ok
DIB RSE ETCH EWS
|

VRDS-20 |
3. Laser diode check
(lop (Intensity Optimum) check)
Connect a DC voltmeter to both ends of R407 on SERVO
PCB. Measure the DC voltage while playing a disc to check
that the measured value does not exceed the lop value
indicated on the pickup by 10mA. (I= measured value/22}
If the measured value is higher than that indicated, the
pickup may be damaged.
* Pay special attention that parts are not damaged by
static electricity.
@How to read numbers on sticker attached to the pickup
(Example)
KSS-151A
11191
646
Serial No.
lop value 64.6mA
DC voltmeter
3. -¥-Y44A-— kK OWBF x 7
(lop (intensity Optimum) (BFE)
(Ey 7 Ty SIAR SP RITO CE)
DC RIVE X-F-XSERVO PCB ® R407 O lyn ic hexe sd 4.
PLAY POMRBL MEL. CORED 6 mR LK
(1 = gu IE / 22) Dey 77 vy SCRRETHS lop fiik 0
TOMALLEMIMNL TORO LC ERMERT 5. MIMNOWAI. WHA
UTS BHEPED 5 Se
xR TERT SIL.
OCs IT vy TRAY -NORAA
(Fil)
KSS-151A
11191
646
YY FILNo.
lop {8 64.6mA
SERVO PCB
4. Anti-shock bracket
To protect the laser pickup mechanism from shocks and
movement during transit, it is secured by a special anti
-shock bracket. Before starting operation, be sure to
release this bracket, which is accessed from the bottom.
4. ARREST
AAEM GORDO S Cy 77 y TERS tev, Be
LTH VET. AMEMIES USES, BRE
LTC HRS
ects
a
y
ag
e
| wien

| VRDS-20 _
4-1 SERVO ADJUSTMENT 4-1 +I
TEST
DISC:
YEDS-18
or
MCD-111
(Except
4-1-6
and
FAKFIAD:
YEDS-18#KILMCD-111
(4-1-6HkO
4-1-7)
4-1-7
€BRS)
V404 R407
V405 | F.GAIN |
v401
aS) 1
TP1 V402
[* |
[6{ GNO |
SERVO PCB
Fig. 4-6
VOLTAGE CONVERSION
Be sure to remove the power cord from the AC outlet
before repositioning the voltage converter switch.
1. Locate the voltage selector on the rear panel.
2. Using a flat-bladed screwdriver, set to the appropriate
230 V or 120 V position according to your area.
VOLTAGE
SELECTOR
230V
(a)
120V

VRDS-20 |
4-1-1 Checking the pickup actuator operation
Before loading the disc, turn the power ON and check
that the pickup actuator moves up and down three times.
(If the pickup is not at inside on the disc, perform the
above operation after moving the pickup to the inside.)
4-1-2 Sled balance adjustment
1. Adjust V405(S.BAL) for OV potential between TP4
pin 1 and TP4 pin 2(GND).
4-1-3 Tracking balance adjustment
1. Connect the oscilloscope between TP1 pin 4(TE1) and
TP1 pin 6(GND), and press the SEARCH (<4orP> )
button.
2. Adjust V401(T.BAL) so that the upper and lower
amplitudes of the tracking error signal waveform
become equal above and below OV.
4-1-4 Focus balance adjustment
1. Connect the oscilloscope between TP1 pin 5(RF) and
TP1 pin 6(GND).
2. In the play mode, and adjust V402(F.BAL) so that
the waveform on the oscilloscope becomes maximum.
00404
WILY)
WR ‘\)
\}
)
MA
\ WN
HN
nit
AWN
AAA
Wy
AX
400006
Ss
41PeE sy IF ye SP OF aAL—9 BEF cD
BRON 77 vy SP 7Fat—-F-M38BEFHTACE,
(Cy 7 Fy TSHBRARMK BOE Sd. RABE Lacey
Ale) FA ATURE LEW S
41-2Aby KFNGV ARB
1. TPADIBEYE TPAD2ZBE Y (GND) MOM EAOV Ic
BK IZ V405(S.BAL) EHMETS.
41-3 b Sy FYING YRBE
1. TPID4HEY(TE1)E TPIMDEGBREY (GND) ica va
RI-DPEGEL. SEARCH DI VV (4d EKIS PH) LH,
2G FVY FLIES OMEMOV EHIMCHRIS & 5 V401
(T.BAL) #3 ¢ 4.
41-474 -AZNDVYARE
1. TPIOSHEY(RF)é TPIODG6BEY (GND) ica va
AIN-TRERT S.
2. PLAYIKKE CA Y AAD —SORMARA ILI S KITV 402
(F.BAL) © iE o 3.
Ny
MY
WN
iM)
ANY)
)
Maximum
M)
Fig. 4-8
4-1-5 Focus offset check
1. After adjusting the focus balance, stop the player. Check
for an offset voltage of 50mV or less at TP3.
If reading values are out of spec, adjust V402 (F.BAL)
again.
4-1-4574 -HAADEy hE
lL. P#-HAND VY ARRMESTOP IRAE LC TP3OA7t yb
HEA 5SOMVALE CHS IL EHTS.
4 LABILA 6 UBS BE V402 (F.BAL) 2H S.

4-1-6 Focus gain adjustment (Use YEDS- 18)
1. Apply 1.16kHz/3.5Vp-p to TP1 pin 1(FE2) from
an external OSC via 100k resistor.
2. Adjust V404(F.GAIN) so that phase at TP1 pin 2
(FE1) is 90° with respect to that of the external OSC
during playback.
Oscillator
1.16KHz/3.5Vp-p
Oscilloscope
| VRDS-20 _
4-1-6 74 —-AATA VIBE (YEDS- 181)
1. ABBOSC & Y 100k Q OF RE LT 1.16kHz/3.5Vp-p®
{224 7P1 O01 BEY (FEQZIZCANTS,.
27 FARK TPL O 2B Y (FEI EAM OSC EMA
90° inte Zk 3 tt V404 (F.GAIN) &3H4 + Z,
SERVO PCB
Fig. 4-9
4-1-7 Tracking gain adjustment (Use YEDS- 18)
1. Apply 1.7kHz/4Vp-p to TP1 pin 3(TE2) from an
external OSC via 100k Q resistor.
2. Adjust V403(T.GAIN) so that phase at TP1 pin 4
(TE1) is 90° with respect to that of the external OSC
during playback.
Oscillator
1,70kH2/4Vp-p
Oscilloscope
4-1-7 KSy FYTT4 VIBE (YEDS- 1816)
1, ABBOSC KY 100k Q OHA LT 1.70kKH2/ 4Vp- p O18
BETPIDZSBEYV (TEI ANTS.
2 TVA TPIO4BE Y (TEL) EWM OSC & OLED
90° Ix H5k5 it V403 (T.GAIN) £39 3.
SERVO PCB
Fig. 4-10

VRDS-20 |
4-2 AUDIO ADJUSTMENT 4-7 470%
. Output level
HALAIL
DISC: YEDS-18 (MCD-111)
TRACK No. } 347
FREQUENCY Bik 2%
SPECIFICATIONS
0.3Vrms (UNBAL)
0.3Vrms (BAL)
REMARKS
i %
load impedance :
BHIVYE-FYA:
50k Q2 (UNBAL)
600 Q (BAL)
. Channel level
difference
Fe VRIVLSIVE
1.0dB or less
. DC offset
adjustment _
DCAD» bE
0 + SmV (UNBAL)
Adjust V151 (bch),
V251 (Rech) on AUDIO
PCB so that the offset
voltage becomes OmV.
AI» bBEAMOMVIC
&HSEKDAUDIO PCB
V151(Leh), V251 (Reh)
ERTS.
. Harmonic
distortion
Bake
. Frequency
response
FEROS TE
. S/N ratio
SAN IE
20Hz~20kHz
0.004 % or less
Within + 1.0dB
100dB or better
AOOHz HPF in
20kHz LPF in
reference level: 1kHz
DIN AUDIO
(Use SHIBASOKU 725
or equivalent)
. Channel
separation
Feely
BNL-Yay
95dB or better
DIN AUDIO
. Emphasis effect
LY 7 YAR
10
AUDIO PCB
— 9.0 = 1.0dB (YEDS-18)
~ 20 + 1.0dB (MCD-111)
reference level: 1kHz
Fig. #-11