Sony TC-204SD User manual

Power requirements:
Power consumption:
Recording system:
Tape speed:
Fast forward and
rewind time:
Record Bias
frequency:
Signal to noise
ratio:
Total harmonic
distortion:
Frequency response:
SPECIFICATIONS
100, 110, 120, 127, 220 or 240V ac,
50/60 Hz (E and AEP Model)
240V ac, 50Hz (UK Model) Inputs:
8W
4-track 2-channel stereo
4.8cm/s (1-7 ips)
Approx. 90 seconds (by C-60)
Outputs:
105 kHz
DOLBY NR OFF
With Ferri-Chrome Cassette
59 dB at peak level (NAB)
50 dB (DIN)
With chromium dioxide cassette
55 dB at peak level (NAB)
With regular cassette
53 dB at peak level (NAB)
DOLBY NR ON
Improved 5dB at 1 kHz, 10 dB above 5kHz
1.7%
DOLBY NR OFF
With Ferri-Chrome Cassette and chromium
dioxide cassette
20-16,000 Hz (NAB)
40-15,000 Hz +3 dB (NAB)
40-15,000 Hz (DIN)
With regular cassette
20-14,000 Hz (NAB)
40-12,000 Hz (DIN)
‘Dolby’ and the double-D symbol are the trade marks
of Dolby Laboratory Inc.
Noise reduction system
Manufactured under license from Dolby Laboratory Inc.
Wow and flutter:
Record/playback connector:
Dimensions:
Weight:
0.09 % (RMS. weighted NAB)
+0.2 % (DIN)
MIC (phone jacks) .......cccceeesesseereeree ee 2
sensitivity -72dB (0.2 mV)
for low-impedance microphone
LINE
IN
(stereo
binaural
jack)
..........
1
(PhONO jacks) ........eceeeeee eee 2
sensitivity -22dB (0.06 V)
input impedance 100 k2
LINE
OUT
(phono
jacks)
.......ceeeeee
2
output
level
OdB
(0.775
V)
at
load
impedance
100
k2
with
LINE
OUT
level
control
at
“10”
suitable
load
impedance
more
than
10
k2
HEADPHONES.
........c:seeeeeeeereeeeerentnee
ott
1
suitable
load
impedance
8
22
Input impedance fess than 10 kQ
Output impedance less than 10 kQ
Approx. 430(w) x 160(h) x 325(d) mm
16 7h(w) x 6 14(h) x 12 34(d) inches
Approx. 8kg (17 tb 10 0z)
SERVICE MANIIAL

TC-204SD
SECTION 1
OUTLINE
1-1. BLOCK DIAGRAM
D3
a
Nay,
LINE IN HEADPHONES
FRONT Vx? METER AMP
LINE IN [Qe WW
(STEREO)
LEVEL
METER
MIG
Q103, 104, 106}
LINE
R181 By
LINE QUT
RPH101 =~
R405
PLAYBACK
LEVEL
y
PB EQ
T301
VOLTAGE _ | D801~304
REP es B+ REGULATOR =| Se
Q301 =» POWER Ac IN
oe
MOTOR
SERVO. my
D 3
MOTOR 306~309
D-O13F
1-2. NOTES ON THE MOLDED CHASSIS
The TC-204SD uses a molded chassis. The
following notes should be taken in serving the set.
1) Use the Diamond Oil No. 440 or equivalent.
2) Use the SONY Grease No. SG-101 or equivalent.
3) Do not tighten PTPWH washer-head self-tapping
screws excessively. Use larger-size(larger diameter)
screws when the screw holes of the molded
chassis becomes loose.
4) The spring which winds round the capstan-shaft
bearing should contact between the reel-table
frame and the pinch roller for the chassis-ground-
ing purpose.

TC-204SD
SECTION 2
ADJUSTMENT
2-1.
MECHANICAL
ADJUSTMENTS
Head
Height
Adjustment
1.
Make
an
adjustment
cassette
as
shown
below.
ome
=
Cut out hatched
portions.
C-120
tape cassette
2.
Viewing
from
the
top,
tape
curl
and
tape
bends
should
not
exist
at
the
arrowed
portions.
—
Playback
Mode
—
teas
erase
head
pinch
roller
record/playback
head
3.
When
a
tape curl
exists
at
the
record/playback
head,
adjust
the
head
height
by
using
adjustment
shim
or
washer.
record/play back
head
adjustment shim:
3-§13-237-01
t=0.1mm
1
3-513-237-1711
t=0.2mm
|
es)
2
—
adjustment shim or washer
4.
When
a
tape
curl
exists
at
the
erase
head,
adjust
the
head
height
by
adjusting
the
screw
at
the
tape
guide
side.
Fast
Forward
and
Rewind
Torque
Adjustment
Specification:
Fast
Forward
and
Rewind:
55—95
g-cm
(0.77—1.32
oz-inch)
If
necessary,
bend
the
spring
as
shown
below.
flywheel
spring
Back Tension Torque Adjustment
— Playback and PAUSE modes —
tape cassette
for adjustment
Wrap tape 10 turns.
oN
A( YS
/ ‘ /
Ke eee
,
\
Cut out here.
2.5~49-cm (0.03~0.06 oz: inch)
at 4.8cm/s (173 ips)
209 tension gauge
Unplug power cord and adjust spring hooking
position to obtain the specified value.
supply reel spindle.
adjust spring
hooking position.
tension lever

TC-204SD
2-2. ELECTRICAL ADJUSTMENTS AND
MEASUREMENTS
PRECAUTION
1. Clean the following parts with an alcohol
moistened swab: ;
* record/playback head * pinch rollers
* erase head « rubber belts
* cap stans * idlers
2. Demagnetize record/playback head with a
head demagnetizer.
3. Do not use magnetized screwdriver for
adjustments.
4. After the adjustments, apply a small amount
of a locking compound to the parts adjusted.
5. The adjustments should be performed in the
order arranged in this service manual.
6. The adjustments and the measurements
should be performed for both L-CH and R-CH
with rated power supply voltage unless
otherwise specified.
7. The record and playback level adjustments
should be carefully performed.
8. Tapes required:
1) blank tapes (completely erased with bulk
eraser)
SONY CS-10 (HF)
CS-20 (CrO2) with two extra holes
CS-30 (Fe-Cr)
2) test tapes
SONY P-4-A81S (6.3 kHz, -10 dB)
P-4-A82 (10 kHz, -10 dB)
P-4-L81 (333 Hz, 0 dB)
WS-48 (3 kHz, 0 dB)
9. The switches and the controls should be set
as follows unless otherwise specified.
DOLBY NR switch: OFF
LIMITER switch: OFF
LINE control: MIN
MIC control: MIN
TAPE SELECT switch: NORMAL
LINE OUT control: MAX
10. Standard record:
Supply the specified input signal level to the
input jack and set the MIC or LINE control
to obtain the specified output signal level.
Set the LINE control to MIN when MIC
input is used or set MIC control to MIN
when LINE IN is used.
Normal Input Level
die
3000 10K
input level Svnde ~104B
(0.77 mV) (0.25 V)
Normal Output Level
Pine ou]
load impedance 100 kQ
0dB
Tape Speed Adjustment
Procedure:
Mode: Playback
speed checker
SONY LMF-30
WS-48
(3kHz, 0dB)
LINE OUT
WS-48 sat
(3kHz,
OdB)}
digital
frequency
counter
LINE OUT
Adjust R602 (R607) to obtain specified value.
Specification:
speed checker digital frequency counter
Frequency difference between beginning and end
of tape should be within | % (30Hz).
Adjustment Location:
R602
(R607)
servo board
R607: Serial No. 17651 and later (E Model)
Serial No. 15651 and later (AEP Model)
Serial No. 17151 and later (UK Model)

_TC-2045D _
PAUSE Timing Adjustment
— Stop Mode —
1.
The
take-up
reel
and
the
pinch
roller
should
stop
at
the
same
time.
If
necessary,
bend
the
spring
as
shown below.
pinch roller (lo 0)
;
Adjust by bending here.
Motor
Switch
(S603)
Position
“Adjustment
—
Stop
Mode
—
1.
Loosen
the
adjustment
screw
and
adjust
the
switch
position
so
that
the
switch
leafs
becomes
6
+0.5mm
(1342)
as
show
below.
_
After
the
adjustment,
secure
the
screw
with
a
suitable
looking
compound.
motor switch (S603)
adjustment
screw
brake release plate
Muting Switch (S602) Position Adjustment
— Stop Mode —
1. Loosen the adjustment screw and adjust the switch
position so that the gap of the switch contacts
becomes 1.0 + 0.5 mm.
1.040.5mm muting switch (S602)
contact
record lock plate
Timing Switch (S601) Position Adjustment
— Stop Mode —
1. Loosen the adjustment screws and adjust the posi-
tion of the timing switch circuit board so that the
muting lever just contacts the switch hole and the
switch starts to move.
2. After the adjustment, secure the screws with a
locking compound.
timing switch
(S607)
adjustment screw
adjustment
screw

TC-204SD
MEMO

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|
T¢C-204SD
TC-204SD
|
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4. Playback Equalizer Adjustment 6. Record Level Adjustment
3. Playback Level Adjustment
2. Record/playback Head Azimuth Adjustment
Procedure: Procedure: Procedure: Procedure:
1. Mode: Playback 1. Mode: Playback 1. Mode: Standard record (See page 6 .)
1. Mode: Playback
P-4-L81
TAPE
SELECT
switch:
NORMAL
af
oie
ne
(333
Hz,
0
dB)
P-4-A82
chy
ose
(10kHz,
-10aB)
10kQ.
oO
attenuator
P-4-A81S
otto
Mi
psezoke)
-A81
(6.3kHz, -10dB)
O
LINE OUT
2dB (0.95 V) LINE OUT ei, 1081026 Vi
: rede 2. Mode: Playback
Adjust R125 (L-CH) and R225 (R-CH) to obtain _ Mode: Playback racers . ie
portion
2 dB (0.95 V) VTVM reading.
TAPE SELECT switch: CrO2 or Fe-Cr
. Assure that the LINE OUT level does not change
when the mode is changed from playback to stop
several.times.
P-4-A82
(10kHz, -10dB)
LINE OUT
kE
OdB (0.775 V)
Adjust R153 (L-CH) and R253 (R-CH) to obtain
0dB (0.775 V) VTVM reading.
3. Change the blank tape to CS-20 and CS-30, and
perform the same record and playback procedure.
Measure LINE OUT level.
Specification:
LINE OU
LINE OUT level: 1.5~2.5 dB T
-9.5dB (0.26 V)
(0.92 ~ 1.05 V)
Level difference between channels:
adjustment
|
in
phase
aoe
less
than
1
dB
Adjust
R124
(L-CH)
and
R224
(R-CH)
to
ee
Y)
“
O
eer
on
obtain
the
LINE
OUT
voltage
2.5-6.5
dB
lower
fenhase rac og phase (B-CH) than that obtained in step 1 above.
patter (L) (R) (L)(R)
around the (Fe Pa Sh ny
highest Level drop
VTVM should be within
readings. 0.5 dB.
Oscilloscope patterns
azimuth [Allowance]
Specification:
SONY tape LINE OUT level
eae -0.5 ~+0.5 dB
(0.74 ~ 0.84 V)
Note: If R124 and R224 are moved too much,
repeat the playback level adjustment on
page 7.
.
Assure
that
LINE
OUT
level
difference
does
not
5.
VU
Meter
Calibration
change when the mode is changed from playback
to stop several times. Procedure:
R253
(R-CH)
R153
(L-CH)
1. Mode: Standard record (See page 6.)
af osc
ey VTVM
attenuator 10 kQ 100 kQ. Ee
O
. After adjustment, apply locking compound to the
screw.
record/playback
+ @
pinch roller
LINE OUT
LINE
IN
OaB
(0.775
V)
333 Hz, -10dB (0.25V)
adjustment
screw
2. Adjust R145 (L-CH) and R245 (R-CH) to make
OVU indication.
Specification:

SD TC-204SD |
4. Playback Equalizer Adjustment
Procedure:
1. Mode: Playback
TAPE SELECT switch: NORMAL
P-4-A82
(10kHz, -10dB)
LINE OUT
—5 0B (0.44 V)
2. Mode: Playback
TAPE SELECT switch: CrO2 or Fe-Cr
P-4-A82
(10kHz, -10dB)
LINE OUT
~9.5dB (0.26 V)
Adjust R124 (L-CH) and R224 (R-CH) to
obtain the LINE OUT voltage 2.5-6.5 dB lower
than that obtained in step 1 above.
Note: If R124 and R224 are moved too much,
repeat the playback level adjustment on
page 7.
5. VU Meter Calibration
Procedure:
1. Mode: Standard record (See page 6.)
af ose
€°) VTVM
attenuator 10 kX 100 kQ. #4
oO
LINE OUT
OdB (0.775 V)
LINE IN
333 Hz, -10dB (0.25V)
(@,)| 2. Adjust R145 (L-CH) and R245 (R-CH) to make
OVU indication.
Specification:
6. Record Level Adjustment 7. Record Bias Adjustment
Procedure: Procedure:
1. Mode: Standard record (See page 6 .) 1. Mode: Standard record (See page 6 .)
af osc
af osc blank tape blank tape
€)
SONY
CS-10
€)
SONY
CS-10
Oo
attenuator
Oo
attenuator
oe —_—_—_—_
EAC)
N
333 Hz, —10dB (0.25 V)
LINE IN
1. 1kHz, -10dB (0,25 V)
2.
Mode:
Playback
2
10kHz,
-10dB
(0.25
V)
recorded
portion
LINE OUT
k
OdB (0.775 V)
Adjust R153 (L-CH) and R253 (R-CH) to obtain
0 dB (0.775 V) VTVM reading.
. Change the blank tape to CS-20 and CS-30, and
perform the same record and playback procedure.
Measure LINE OUT level.
2. Mode: Playback
recorded
portion
LINE OUT
Adjust C154 (L-CH) and C254 (R-CH) to obtain
10 kHz-signal level 0.5 dB lower than that of 1 kHz.
Specification:
SONY tape LINE OUT level
ei A -0.5 ~+0.5 dB
Note: When 10kHz output level is too low,
turn the trimmer capacitor counter-
clockwise.
10 kHz signal level is
0dB + 1 dB lower
than that of 1 kHz
signal.
Specification:
CS-20
a0 (0.74 ~ 0.84 V)
C154
(L-CH)
R253 R153
(R-CH) (L-CH)
8. 19kHz Filter Adjustment
Procedure:
1. Mode: Standard record (See page 6 .)
af osc
©) attenuator
oO
LINE OUT
MIC
19 kHz £20 Hz
(-60 dB, 0.77 mV)
Adjust L105 (L-CH) and L205 (R-CH) for
minimum VTVM reading.
TC-204SD

TC-204SD
|
4
|
T¢c-204SD
_TC-204
SECTION 3
DIAGRAMS
Note:
3-1. MOUNTING DIAGRAM @ B+ pattern Serial No.
. E Model Up to 17650
— Conductor Side — AEP Model Up to 1565
. :
UK
Model
Up
to
1715¢
[SERVO AMP BOARD]
i918
rc
)
—~{
20~28
29~32 > 29~32
*
i
aa
hts
‘
[AUDIO
AMP
BOARD]
‘
2
urine
wur/ver
|
WHT/6RW
15,
Ri8i, 281
LINE OUT BRN EL
“4
‘si PL4 PL3 PL2
REC TAPE METER
|WHT/BLK
40,
41
WHT/BRN 1302
HEADPHONES:
ren
he
7301
BRN
C309
ob 1
F | Pp comes cael a Poy
—{29~35 -—— a {29-31
32 Be 38
VY
O g 3 PLS
20 (reo) =) o| SI (S) doce we
a Neal een ton s] g} Fa f (SWITCH
&
WHT/BLK ensor Kok ne
(EFI35-36) “Torey
(REDD
22) WHT
WeRY) (RED)
WHT 4
RED
9
RED =>
[> art te
(WHT) (WHT)
RPHIOL. 201 Gery)) tery)
(PF145-3602A)
50 N28
VU METER(L)'
BRN) (YEL!
50,51) ~<50, 51 EL
scone
21> REO
16 17
£16, 17
WHT WHT/ EBLK
86 TAPE
BIAS ——— SELECT
Low N
WBRND) (GRY)
S3 DOLBY NR ON(FILTER OFF) SS LIMITER ON NORM F
RUB, 213 RI, 21 a t
vv OFF HIGH c
SOKtA) 20K (A) OFF

TC-204SD TC-204SD S<
vt : Note:
Serial No. a
E Model 17651 and later
AEP Model 15651 and later
Note:
Note:
UK
Model
17151
and
later
;
Serial
No.
B+
pattern
E
Model
Up
to
17650
AEP
Model
Up
to
15650
’
UK
Model
Up
to
17150
Q
CSERVO AMP BOARD
[SERVO AMP BOARD]
20~28 TAPE_SPEED
neocon
ORG 4VIO vio
4
(nokta,
Qe 9) (OOOO)
©B®D 0)
69
MOOD)
Op®
FI
98, fOWER 160m4
o
lial an Ce
Co
Q102, 202
Q103, 203
} 2SC632A
[E MODEL]
Q303~305
Q110~112
Q210~212 ; 2SC634A
Q104~108
Q204~208 Q302: 2S8C1384 1C101, 201: CX-064
(UK AEP MODEL)
—
/ PLAN oh AR,
:
EcR,
10111213141516
1718
CN F
(Top view}
Q101, 201 2501362 Q301: 2SC1760 IC601: CX-065
Q109, 209 Q601
2
Q601, 602: 2SC1363 pee etal
WHT/BLK
vio
WHT/Vio.
3
c
ae “K) 12345678
E y Hf €
z
\
CX-O65A
OLB: BoE
ee 30, D101, 201 234564
POLANBRNY
D103,
203
;
1T40
D301~304
$1B01-02
pewio)20
D310,
312,
313
D306~309
D102, 202: 1T22 D305: EQA01-02R D311: SLP2?4B
WHT
(99
cathode
cathode
(BLU) BRND -
ok cathode. ande
ay
i
GD
oh
ae
anode anode
cathode
mode
x sé TAPE
BIAS ——— SELECT. £@
Low pis
$3 DOLBY WR SOMIETLTER OFF) SS LIMITER ON NORM FeCr
oN
OFF HIGH Cr
or q