STR-DE185 - Sony Audio Service Manual (repair manual)

1

US Model

AEP Model

UK Model

With 8 ohm loads, both channels driven, from
40 – 20,000 Hz; rated 100 watts per channel
minimum RMS power, with no more than
0.09 % total harmonic distortion from 250
milliwatts to rated output (Models of area code
US only).

POWER OUTPUT

Models of area code US
Rated Power Output at Stereo Mode
(8 ohms 40 Hz – 20 kHz, THD 0.09 %)

100 W + 100 W

Models of area code AEP, UK
Rated Power Output at Stereo Mode
(

8 ohms 1 kHz, THD 0.7 %)

100 W + 100 W

 1)

1) Measured under the following conditions:

Area code

Power requirements

AEP, UK

230 V AC, 50 Hz

Frequency response

CD, MD/TAPE,

20 Hz – 50 kHz

VIDEO 1, VIDEO 2

+0/–0.5 dB (with bass
boost bypassed)

Inputs (Analog)

CD, MD/TAPE,

Sensitivity: 250 mV

VIDEO 1, VIDEO 2

Impedance: 50 kilohms
S/N

 2)

 : 85 dB

(A, 250 mV

 3) 

)

2) INPUT SHORT.
3) Weighted network, input level.

Outputs

MD/TAPE, VIDEO 1

Voltage: 250 mV
Impedance: 10 kilohms

Bass Boost:

+8 dB at 70 Hz

Tone:

±10 dB at 100 Hz and
10 kHz

Tuning range

87.5 – 108.0 MHz

Antenna terminals

75 ohms, unbalanced

Intermediate frequency

10.7 MHz

Sensitivity

Mono:

18.3 dBf, 2.2 µV/75 ohms

Stereo:

38.3 dBf, 22.5 µV/75 ohms

Usable sensitivity

11.2 dBf, 1 µV/75 ohms

S/N

Mono:

76 dB

Stereo:

70 dB

Harmonic distortion at 1 kHz

Mono:

0.5%

Stereo:

0.8%

Separation

35 dB at 1 kHz

Frequency response

30 Hz – 15 kHz,
+0.5/–2 dB

Selectivity

60 dB at 400 kHz

2003K04-1

© 2003.11

– Continued on next page –

2

COMPONENTS  IDENTIFIED  BY  MARK  0  OR  DOTTED  LINE
WITH  MARK  0  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  PUBLISHED  BY  SONY.

Tuning range

Models of area code US
With 10-kHz tuning scale: 530 – 1710 kHz

 4)

With 9-kHz tuning scale: 531 – 1710 kHz

 4)

Models of area code AEP, UK
With 9-kHz tuning scale: 531 – 1602 kHz

Antenna

Loop antenna

Intermediate frequency

450 kHz

Usable sensitivity

50 dB/m (at 1,000 kHz or
999 kHz)

S/N

45 dB (at 50 mV/m)

Harmonic distortion

1.0 % (50 mV/m,
400 Hz)

Selectivity
     At 9 kHz:

35 dB

     At 10 kHz:

40 dB

4) You can change the AM tuning scale to 9 kHz or

10 kHz. After tuning in any AM station, turn off
the receiver. Hold down PRESET TUNING + and
press ?/1. All preset stations will be erased when
you change the tuning scale. To reset the scale to
10 kHz (or 9 kHz), repeat the procedure.

Power requirements

Area code

Power consumption

US

120 V AC, 60 Hz

AEP, UK

230 V AC, 50/60 Hz

Power consumption

Area code

Power consumption

US

190 W

AEP, UK

210 W

Power consumption (during standby mode)

0.5 W (for models of all area code)

AC outlets

Area code

AC outlets

US

1 switched, 120 W/1A MAX

AEP, UK

1 switched, 100 W MAX

Dimensions

430 

× 145 × 300 mm

(16 

7/8

 

× 5 

6/8

 

× 11 

6/8

 in.)

including projecting parts
and controls

Mass (Approx.)

7.0 kg (15 lb 7 oz)

Supplied accessories

FM wire antenna (1)
AM loop antenna (1)
Remote commander RM-U185 (1)
R6 (size-AA) batteries (2)

Design and specifications are subject to change without
notice.

Part No.

US

4-238-277-0s

AEP

4-238-277-1s

UK

4-238-277-2s

3

Main unit ................................................................................. 4
Remote button description ....................................................... 5

2-1.   Case ..................................................................................... 6
2-2.   Front Panel Section ............................................................. 7
2-3.   Back Panel ........................................................................... 7
2-4.   Main Board ......................................................................... 8

........................................................................ 9

4-1.   IC Pin Description ............................................................. 10
4-2.   Circuit Boards Location .................................................... 11
4-3.   Block Diagram – Main Section – ...................................... 12
4-4.   Block Diagram – Power Section – .................................... 13
4-5.   Printed Wiring Board – Main Section – ............................ 14
4-6.   Printed Wiring Boards – H/P, Outlet Section – ................. 15
4-7.   Schematic Diagram – Main Section (1/2) – ...................... 16
4-8.   Schematic Diagram – Main Section (2/2) – ...................... 17
4-9.   Schematic Diagram – Display Section – ........................... 18
4-10. Printed Wiring Board – Display Section – ........................ 19
4-11. Printed Wiring Board – Power SW Section – ................... 20

5-1.   Case Section ...................................................................... 21
5-2.   Front Panel Section ........................................................... 22
5-3.   Chassis Section ................................................................. 23

......................................... 24

Ω

µF

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.

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 0.5 mA (500 microamperes).
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
instruments.

2. A battery-operated AC milliammeter. The Data Precision 245

digital multimeter is suitable for this job.

3. Measuring the voltage drop across a resistor by means of a VOM

or battery-operated AC voltmeter. 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)

4

This section is extracted
from instruction manual.

GB

Use this page to find the location of buttons that are
mentioned in the text.

r

NAME 5 (18)

R

R

AM 8 (13, 14)
BALANCE L/R q; (12)
BASS +/– wa (12)
BASS BOOST ql (12)
CD qg (8, 12)
DIRECT wg (13)
DISPLAY  qa (12, 16)
Display 9 (11-16, 18, 19)
FM 6 (13, 14)
FM MODE wd (14)

IR (receptor) 2 (4, 22)

SHIFT wh (15)
SLEEP (models of area code U)

4

 (19)

SPEAKERS A wj (10, 12)
SPEAKERS B wk (10, 12)

TREBLE +/– w; (12)
TUNER qh (8, 12-15, 18)
TUNING/CHAR +/– ws (14, 18)
VIDEO 1 qs (12)
VIDEO 2 qd (8, 12)

?/1

 (power) 1 (11, 13, 23)

MASTER VOLUME qj (12, 20)
MD/TAPE qf (8, 12)
MEMORY/ENTER wf (13, 15,

18)

MUTING qk (12, 20)
NAME 5 (18)
Numeric buttons 3 (13)

PHONES wl (12, 21)
PRESET/PTY SELECT +/–

(models of area code CEL,
CEK) 7 (15, 16)

PRESET TUNING +/– (models of

area code U) 7 (15, 23)

PTY (models of area code CEL,

CEK) 4

 

(16)

1

2

3

456

7

8

9q;

qa

qs qd qf qg qh

qj

qk

ql

w;

wa

ws

wd

wf

wg

wh

wj

wk

wl