Sony TC-WR545 Primary User manual

SERVICE MANUAL
Photo : TC-WR545
TC-WR45/WR741
US Model
Canadian Model
TC-WR545/WR74 1
AEP Model
UK Model
E Model
Australian Model
TC-WR545
Model Name Using Similar Mechanism | TC-WR535
Tape Transport Machanism
Type
DECK A} TCM-190RA12CL
TCM-WR545 : TCM-190RB12CL
DECK B
TCM-WR741 : TCM-190RB52C
SPECIFICATIONS
4-track 2-channel stereo
Approx. 90 sec. (with Sony C-60
cassette)
Bias | AC bias
Signal-to-noise ratio (at peak level and weighted)
Cassette Type IV Type Il Type I
(Dolby NR
OFF) 58 dB 57 dB 55 dB
S/N ratio improved (approximate values)
with Dolby B NR on: 5 dB at 1 kHz; 10 dB at 5 kHz
with Dolby C NR on: 15 dB at 500 Hz; 20 dB at 1 kHz
Recording system
Fast winding time
Harmonic distortion
0.4% (with Sony Type I, 160 nWb/m,
315 Hz, 3rd H.D.)
1.8% (with Sony Type IV, 250 nWb/m,
315 Hz, 3rd H.D.)
Frequency response (Dolby NR OFF)
Type IV Type I Type lI
cassette cassette cassette
30 - 18,000 Hz }30- 17,000 Hz | 30 - 15,000 Hz
(43 dB, TEC) {G@3dB,IEC) | (43 dB, IEC)
30 - 13,000 Hz
[+3 dB (-4 dB)
recording]
Type IV: Sony Type IV (METAL)
Type Il: Sony Type IJ (HIGH)
Typel: Sony Type I (NORMAL)
Wow and flutter +0.14% W.Peak (IEC)
0.08% W.RMS (NAB)
+0.19% W.Peak (DIN)
— Continued on page 2 —
Dolby noise reduction manufactured under license from
Dolby Laboratories Licensing Corporation.
“DOLBY” and the double-D symbol 90 are trademarks of
Dolby Laboratories Licensing Corporation.
STEREO CASSETTE DECK
SONY.

Inputs
(phono jacks) Input impedance 47 k ohms
Outputs
Line outputs
(phono jacks)
0.5 V ata load
impedance of
47 k ohms
Load impedance | Over 10 k ohms
Output level 1 mW at a load
impedance of
32 ohms
US, Canadian model : 120V AC, 60Hz
UK model : 240V AC, 50Hz
Australian model : 240V AC, 50/60Hz
AEP, German model :
220-230V AC, 50/60Hz
E model :
120, 220 or 240V AC adjustable,
50/60Hz
25W
EXCEPT UK, Australian model :
Approx. 430 x 123 x 290 mm
(w/h/d)
(17 x 47/s x 11 !/2 inches)
UK, Australian model :
Approx. 430 123x300 mm
(w/h/d)
(17X474x 117A inches)
including projecting parts and
controls
Approx. 4.5 kg (9 Ibs 15 0z)
Rated output
level
Headphones
(stereo phone jack)
(TC-WR545 only)
General
Power requirements
Power consumption
Dimensions
Mass
Supplied accessories
Audio connecting cords (2)
Design and specifications are subject to change without
notice.
MODEL IDENTIFICATION
(Specification Label)
SONY:
STEREO CASSETTE DECK
MODEL NO. Rss aaa
: AC 120V 60Hz
US, Canadian model
UK model : AC 240V 50Hz
Australian model! : AC 240V~50/60Hz
AEP, German model : AC 220-230V~50/60Hz
E model : AC120, 220, 240V~50/60Hz
TABLE OF CONTENTS
Section Title Page
Specifications :++seresesesereeeeteeteeeeteereeteese teeter eseeeseees l
Safety Check-out (US Model) SOrPereeeereeer re rere rere rere rr eee) 3
1. GENERAL
Identifying the Parts on the Front Panel s++r+t++trrrsrrtetttteee 4
2. DISASSEMBLY
2-1 . Front Panel errr rrr errr tree rere ee ee eee eee ee eee 5
2-2. Mechanism Deck eer rr rrr rer rr rrr rr errr rere rrr reer reece 5
2-3. Capstan Motor, Reel Motor ssrrrrtrrrtrrerritrsisesessee 6
2-4. Head, Pinch Rollers::sssressrereertseeeeeeeeeteeeneeeeneeeey 6
3. ADJUSTMENTS
3-1. Mechanical Adjustments :+rrrsttrrrrrereertrsereterseersersees ay
3-2. Electrical Adjustments «-++1+esseseereeeeeteeterteerierieees 7
4. EXPLANATION OF IC TERMINALS --+-e erste 11
5. DIAGRAMS
5-1. Block Diagram cece ener enon scree teen rset ne enereeseeenonsesecure 13
522) Circuit Board Location Sererrerrrrrr rrr errr errr e rrr 16
5-3. Printed Wiring Boards (System Control Section)-++++-- 17
5-4. Schematic Diagram (System Control Section):**+*+++*- 21
5-5. Schematic Diagram (Audio Section) srrrrsrrrrtrrtttrerees 27
5-6. Printed Wiring Boards (Audio Section):**++rstrtrrete"* ep
6. EXPLODED VIEWS
6-1. Chassis Section eee e cece tere nme eee e aren eee sereesenereneueeeenes 37
6-2. Front Panel Section Deemer meen e nse et tere an nsosscoesesaeeeseeee 39
6-3. Mechanism Section l deere ence recone eta a en eee nese e seen enee 40
6-4. Mechanism Section 2esrrcerersssseerteseeteeeeecesessenennes A]
7. ELECTRICAL PARTS LIST -sr--:ceecceceeceeeeseeeeeeeeeerees 42
TC-WR545, TC-WR741

SAFETY CHECK-OUT (US Model)
After correcting the original service problem,
perform the following safety check before releasing
the set to the customer:
Check the antenna terminals, metal trim, “‘metallized”’
knobs, screws, and all other exposed metal parts for
AC leakage. Check leakage as described below.
LEAKAGE TEST
The AC leakage from any exposed metal part to
earth ground and from all exposed metal parts to any
exposed metal part having a return to chassis, must
not exceed 0.5mA (500 microampers). Leakage
current can be measured by any one of three
methods.
1. A commercial leakage tester, such as the
Simpson 229 or RCA WT-540A. Follow the
manufacturers’ instructions to use these instru-
ments.
2. <A battery-operated AC milliammeter. The Data
Precision 245 digital multimeter is suitable for
this job.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK A OR DOTTED
LINE WITH MARK A ON THE SCHEMATIC DIAGRAMS
AND IN THE PARTS LIST ARE CRITICAL TO SAFE
OPERATION. REPLACE THESE COMPONENTS WITH
SONY PARTS WHOSE PART NUMBERS APPEAR AS
SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-
LISHED BY SONY.
3. Measuring the voltage drop across a resistor by
means of a VOM or battery-operated AC volt-
meter. The “limit” indication is 0.75 V, so
analog meters must have an accurate low-
voltage scale. The Simpson 250 and Sanwa
SH-63Trd are examples of a passive VOM that
is suitable. Nearly all battery operated digital
multimeters that have a 2V AC range are
suitable. (See Fig. A)
To Exposed Metal
Parts on Set
AC
voltmeter
ialagee (0.75 V)
= Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.
ATTENTION AU COMPOSANT AYANT RAPPORT
A LA SECURITE!
LES COMPOSANTS IDENTIFIES PAR UNE MARQUE /\
SUR LES DIAGRAMMES SCHEMATIQUES ET LA LISTE
DES PIECES SONT CRITIQUES POUR LA SECURITE
DE FONCTIONNEMENT. NE REMPLACER CES COM.-
POSANTS QUE PAR DES PIECES SONY DONT LES
NUMEROS SONT DONNES DANS CE MANUEL OU
DANS LES SUPPLEMENTS PUBLIES PAR SONY.

SECTION
1
This
section
is
extracted
from
GENERAL
instruction
manual.
Identifying
the
Parts
on
the
Front
Panel
|
Remote control sensor*
3} 14) 15] 16) [7J18I19)
18) 17) 16) 15) [14
(The illustration shows the TC-WR545.)
For details, refer to the page number(s) indicated in
parentheses.
POWER switch Tape operation buttons
Deck A <4 (leftward fast-winding)/AMS***/RMS**— button
[3] COUNTER RESET button (deck A) PP (rightward fast-winding)/AMS***/RMS**+ button
RMS operation buttons (TC-WR545 only) Mi (stop) /(RMS**) CLEAR button
RMS/START button <] (reverse play) /(RMS**) BACK button
SET button [> (forward play) /(RMS**) FRONT button
CHECK button If PAUSE button (deck B only)
DISPLAY button O REC MUTE (record muting) button (deck B only)
Display panel @ REC (recording) button (deck B only)
[6] AUTO CAL button (TC-WR545 only) [14] MPX FILTER switch (TC-WR545 only)
COUNTER RESET button (deck B) DOLBY NR (Dolby noise reduction) switch
SYNCHRO DUBBING buttons DIR (direction) MODE switch
HIGH button PHONES jack (stereo phone jack) (TC-WR545 only)
NORMAL button & (eject) button (deck A)
[9] REC (recording) LEVEL control
Deck B * Remote control sensor
BALANCE control You can remotely control this cassette deck with:
(12) & (eject) button (deck B) — A remote commander that came with a Sony amplifier
or receiver if it has the f mark and cassette deck control
capability.
— Any optional Sony remote commander with the EJ mark
and cassette deck control capability.
** Random Music Sensor (TC-WR545 only)
“** Automatic Music Sensor
6

SECTION 2
DISASSEMBLY |
2-3. CAPSTAN MOTOR, REEL MOTOR
Note : Follow the disassembly procedure in the numerical order given.
@ +PTPWh2 x 23
CASE
Unscrew the four case attachment screws M3 X 8 and
remove the case.
2-1.
FRONT
PANEL
\
@
Fitting
base
E model only
FRONTPANEL @- ©
VOLTAGE SELECTOR When installing, pull the FR i)
capstan
belt
and
put
and
put
around
claws.
When installing, pull the |
around claws.
VOLTAGE
SELECTOR
@ Remove the flat cable.
© Remove the front Panel
@ claw @ Connectors
@ Capstan motor M1 (DECK A)
M3 (DECK B)
Ground plate
2-2, MECHANISM DECK @ MD(A)board (DECK A)
MD(C)board (DECK B)
@ Press the EJECT button.
@ Reel motor M2 (DECK A)
M4 (DECK B)
Remove the cassette holder
Belt (FR)
© +P2.6x28
2-4. HEAD, PINCH ROLLER
@ Cassette lid
3] Claw
© BVIP2.6x8
1) Claw
@ Head base assy
HP101(DECK A)
HRPE101(DECK B)
Mechanism deck
6 : @ BVTP2.6 x 8
@ Lever (pinch lever REV) assy @ Lever (pinch lever FWD) assy

SECTION 3
ADJUSTMENTS
3-1. MECHANICAL ADJUSTMENTS
PRECAUTION
1. Clean the following parts with a denatured alcohol-moistened
swab:
record/playback/erase head
rubber belts
idlers
2. Demagnetize the record/playback head with a head demagnetizer.
(Head demagnetizer do not approach for the erase head.)
3. Do not use a magnetized screwdriver for the adjustment.
4. After the adjustments, apply suitable locking compound to the
parts adjusted.
5.The adjustments should be performed with the rated power
supply voltage unless otherwise noted.
pinch roller
capstan
Torque Measurement
Meter reading
30 to 65g * cm
CQ-102C
(0.42
to
0.9
oz
*
inch)
Forward
DECK A: 1 to 6g * cm
(0.014 to 0.083 oz ¢ inch)
Forward
back
tension
Reverse
back
tension
FF/REW CQ-201B
3-2. ELECTRICAL ADJUSTMENTS
CQ-102C
DECK B : 2 to 9g * cm
(0.03 to 0.12 oz * inch)
30 to 65g * cm
(0.42 to 0.9 oz * inch)
1 to 6g *cm
SOneR (0.014 to 0.083 02 « inch)
70 to 120g*cm
(0.98 to 1.66 ozeinch)
PRECAUTION
1. The adjustment should be performed in the publication.
(Be sure to male playback adjustment at first.)
2. The adjustments and measurement should be performed for both
L-CH and R-CH.
@ Switch position
DOLBY NR switch : OFF
DIR MODE switch =
® Standard record position :
Deliver the standard input signal level to input jack and set the
REC LEVEL control to obtain the standard output signal level
as follows.
— Record Mode —~
AF OSC
VTVM
Q attenuator 10k Q
ono oF
I] ooo |
[cee |
LINE OUT
LINE IN
Standard Input Level
source impedance
input signal level 0.5V ( — 3.8dB)
Standard Output Level
Output terminal LINE OUT
output signal level 0.5V ( — 3.8dB)
Test Tape .
|_Tape | Contents | Use
P-4-A 100 10kHz, — 10dB Azimuth Adjustment
P-4-L300 315Hz, 0dB PB Level Adjustment
WS-48B 3kHz, 0dB Tape Speed Adjustment
OdB=0.775V
Test Mode
1. Insert a short-circuit plug into TP801 (2P) and turn ON the
power switch. (Earth pin 9 of IC801 and turn ON the power
switch.)
At first, all the fluorescent tubes light up, then the system returns
to normal display. (However, “OOOO” is not displayed on the
counter. )
2. To release the test mode, remove the short plug and turn off the
power switch.
3. Remove the short plug after completion of adjustment.
Record/Playback Head Azimuth Adjustment
Procedure :
1. Forward playback Mode
test tape
P-4-A100
(10kHz, — 10dB)
VTVM
LINE OUT
2. Turn the adjustment screw for the maximum output levels. If
these levels do not match, turn the adjustment screw until both of
output levels match together within 1dB.
L-CH
peak
within
ix R-CH
peak
Screw
—
screw
position
position L-CH R-CH

3. Playback Mode
test tape
P-4-A100
(10kHz, — 10dB)
oscilloscope
nphase 45° rT j
good
4, Change the reveres playback mode and repeat the steps 1 to 3.
5. After the adjustment, lock the adjustment screws with suitable
locking compound.
Adjustment Location : — record/playback head —
reverse side forward side
adjustment screws
Tape Speed Adjustment
Procedure :
— Forward Playback Mode —
test tape
WS-48B
(3kHz, OaB)
LINE OUT
(high speed adjustment)
1. Connect @ pin of IC801 to ground.
2. Set to FWD playback mode.
3. Keep on pressing the HIGH SPEED DUBBING switch.
4. Adjust RV72 so that the frequency counter reading becomes
6,000 + 20Hz.
(normal speed adjustment)
1. Set to FWD playback mode.
2. Adjust RV71 so that the frequency counter reeding becomes
3,000 + 10Hz.
Frequency difference between the beginning and the end of the tape
should be within 3%.
Frequency difference between the deck A and deck B the beginning
of the tape should be within 1.5%.
Adjustment Location : AUDIO board
Playback Level Adjustment
Procedure :
— Forward Playback Mode —
test tape
P-4-L300
(315Hz, 0dB)
LINE OUT
Adjust RV11(L-CH) and RV21(R-CH) so the VITVM reading
becomes the adjustment limits below.
Adjustment Value :
LINE OUT level : — 7.7 = 0.5dB (0.301 to 0.338V)
Level difference between channels : within 0.5dB
Confirm the LINE OUT level does not change in playback mode
while changing the mode from playback to stop several times.
Adjustment Location : AUDIO board

Bias Consumption Current Adjustment (TC-WR545 only)
This adjustment should be performed when replacing the head assy
or the bias oscillating transformer (T81, T91).
Procedure :
():R-CH
a - digital
biank tape voltmeter
CS-413
| set a atl
LINE IN
ne signal
1..Connect the digital voltmeter to test point TP81.
2. Set RV81 (RV91) to mechanical center.
3. Set to FWD record mode.
4, Adjust T81 (T91) so that the digital voltmeter reading becomes
minimum. oe
Adjustment Value : Maximum 220mV
Adjustment Location : AUDIO board
Record Bias Adjustment
Setting :
REC LEVEL control : standard record position (Refer to page 7.)
Procedure :
1. Record Mode
AF OSC
blank tape
CS-123
foe | SI
} 38.8mV( — 260B)
LINE IN
1) 315Hz
2) 10KHz
2. Playback Mode .
VIVM
recorded
portion
ic
Confirm that the 1OkHz playback output is 0 + 0.5dB relative to the
315Hz output. If necessary, adjust RV81 (L-CH), RV9 1(R-CH) :
TC-WRS545, RV12 (L-CH), RV22 (R-CH) : TC-WR741 and
repeat the steps given above.
Adjustment Location ; AUDIO board
Record Level Adjustment
Setting :
REC LEVEL control : standard record position (Refer to page 7.)
Procedure :
1. Record Mode
AF OSC
blank tape
e CS-123
oO GVV——
o—o
— i>
2. Playback Mode
recorded VITVM
portion
ic
Confirm playback the tape recorded become adjustment level as
follows.
If necessary, adjust RV101(L-CH), RV201(R-CH) and repeat the
steps 1 and 2.
LINE OUT
Adjustment Value :
LINE OUT level: — 26 + 0.5dB (36.7 to 41.1mV)
Adjustment Location : MAIN board

— Adjustment Parts Location Diagrams —
{SYSTEM CONTROL BOARD)
Record Level
oF
(1) (R)
RVIO! RVzZ201
DECK-A :
[AUDIO BOARD)
DECK-B : TC-WR545
{AUDIO BOARD]
Bias Consumption Current
Record Blas
en
(R) (L)
AV9I RVE8I
RV72 (HIGH)
RV71 (NORMAL)
RV72 (HIGH)
RV71 (NORMAL)
RV21 (R)
AVIT (L)
T91 (R)
RvV21 (R)
RVit (L)
Tape speed
Playback
Level
Tape speed
Current
DECK-B : TC-WR741
{AUDIO BOARD)
Tere) Bias Consumption
Playback
Level
Bias Consumption Current
Record Bias
en
(A)
RV22 AVI2
RV72 (HIGH)
Tape speed
RV71 (NORMAL)
Playback
Level
RV21 (R)
AVIT (L)

SECTION 4
EXPLANATION OF IC TERMINALS
IC801 CXP82316-039Q
OQ
SIRCS IN
POWER IN
SPEED H/L
A/B
NRO
NRI1
MODE1
MODE2
10 POWER OUT
LIN MUTE
IC MUTE
REALY REC/PB
REC CALO
REC CALI
EQ CALO
EQ CALI
BIAS (B)
Sires signal in terminal.
I] Power OFF. OFF = OV
Power ON/OFF.
Line mute ON/OFF. “L”:ON
Meter mute. “H”:ON
Recording/Playback selector at DECK-B. “L”: Recording
Recording calibration. “H”:ON | |
Bias ON/OFF at DECK-B. “H”:ON
Test mode terminal. “L” : Test mode, “H” : Normal mode
E
4 tw
iC)
a
19
20 METAL(B)
70 w (B)
A/D CTRLO
A/D CTRLI
A/D INO
A/D INI
S. REEL (A)
S. REEL(B)
AMS IN
AMS/BS
RESET
EXTAL
XTAL
Metal tape selector terminal. “H” : Metal
CrOz2tape selectorterminal. “L”’:CrO2
—_—
dKSd —
RO —
oO
dO oO
—
:
AMS signal input terminal.
AMS/BS selector. “L” : BS ON
Reset terminal. Reset : OV
System clock output terminal.
System clock input terminal.
Recording mute ON/OFF. “L” : ON
OSC ON/OFF control. “H” : OFF
OSC H/L control terminal.
22
ZS
4
5 N
iS)
\O
OO With
we
KR
BIAS CALO
BAIS CALI
BAIS CAL2
BAIS CAL3
REC MUTE
OSC ON/OFF
OSC H/L
W
ON
3
3
39
0
oO
~
iN
\ee) Wi Ww
Nn