Sherwood R-725/RDS User manual

SERVICE MANUAL
R-725/RDS + AV-725
AUDIO/VIDEO PRO-LOGIC RECEIVER
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* A PRODUCT OF AV-725 OMITS ONLY TUNER PART TO R-725
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Sherwood.

SAFETY PRECAUTIONS
WARNING
Before servicing this unit, familiarize yourself with the following precautions:
1. Many electrical and mechanical parts in this exposed metal parts of the cabinet, such as
chassis have special safety characteristics that
often pass unnoticed and the protection
afforded by them cannot necessarily be
obtained by using replacement components
rated for higher voltge, wattage, etc.
Replacement parts that have these special
safety characteristics are identified in this
manual and its supplements: electrical
components having such features are
identified by ! in the schematic diagram
and the parts list.
Before replacing any of these components,
read the parts list in this manual carefully. The
use of substitute replacement parts that do
not have the same safety characteristics as
specified in the parts list may create shock,
fire, or other hazards.
. Before returning the set to the customer,
always do an AC leakage current check on the
terminals, screw heads, and metal overlays,
to be sure the set is safe to operate danger of
electrical shock. Plug the AC line cord directly
into a 120 V AC outlet (120 V AC version only).
(Do not use a line isolation transformer
during this check.) Be sure your AC voltmeter
has a sensitivity of 5000 £2 per volt or greater.
Then connect a 1500 {2 10 watt resistor,
paralleled by a 0.15 uF 150 V AC capacitor,
between a known good earth ground (such as
a water pipe, or conduit) and the exposed
metalic is parts, one at a time. Measure the
AC voltage across the combination of a 1500
(2 resistor and a 0.15 ,1F capacitor. Reverse the
AC plug at the AC outlet and repeat AC
voltage measurements for each exposed
metalic part. Voltage measured must not
exceed 0.75V RMS. This corresponds to 0.2
mA AC. Any value exceeding this limit
constitutes a potential shock hazard and must
be corrected immediately.
At 5000 © per volt or greater sensitivity ,
the reading should not exceed 0.75 V.
AC Outlet
AC Voltmeter
Good earth ground, such as
a water pipe or conduct.
0.15 #F 150V AC
Place the probe on each exposed metalic part.

SPECIFICATIONS
a FRONT AMP SECTION
Measuring methods are based on IHFand IEC standard 268-3.
Measurements conditions, unless otherwise noted :
* Output resistive load : 8 ohms/Both channel driven
* Tone(Bass, Treble), Balance, EQ control : Center Position, Other SW's : OFF.
* Nominal input level : 5 mV for MM, 0.5 mV for MC, 500 mV for general purpose inputs.
* Power figures should be kept minimum 10 min. between 15 and 35 c.
* Terminator : 100 ohm for MC, 1 kohm for MM and general purpose inputs.
* Filter : IHF-A filter * R/O: Rated Output
| NO | DESCRIPTION | __ INPUT FREQ. | REMARK | UNIT LIMIT | NOMINAL
' 4 ‘Input Sensitivity AUX ; 1 KHz mV 200+50 | 200+30
MM | 1 kHz mV 2.5+0.5 | 25+03
"2 |Channel Balance AUX 1 kHz/R/O TO -40dB) dB +3 +2
|
|
1
kHz|-40
TO
-60dB/
dB
+6
+4
(3 |Residual Noise AUX 1 kHz) VOL min. mV A ced ||
| 4 Total Harmonic Distortion AUX (500mV) 20Hz) R/O 1W % <0.2 <0.09
| 1kHz - % <0.2 <0.09
! | |_20Hz : % <0.3 <0.2
| 5 (Continuous Average Power AUX | 20Hz 8ohms WwW 130 132
r at (0.2)% THD 1kHz : Ww | 130 132. |
| | 20Hz WwW 130 132
6 IMD(SMPTE) | AUX(500mvV); 60Hz=4 R/O % <0.2 <0.09
ae 7kHz=1 1w % <0.2 < 0.09
| 7 |S/NRATIO, IHF-A FILTER | AUX(500mvV) 1kHz R/O dB >90 | 3>93 |
MM(5mvV) 1kHz R/O dB >68 2i2 |
| 8 |Channel Separation AUX(500mvV) 100Hz| R/O -3dB dB >45 >55
1kHz . dB >45 > 55
10kHz| . dB >40 >45
{ 9 |Function Crosstalk CDSAUX , 1/10 kHz 7 dB >60/40 | >65/45
| ; AUX->MM 1/10 kHz : dB > 60/40 >65/45 |
| MM ->AUX | 1/10 kHz | : | dB > 60/40 > 65/65 |
; 10 |Frequency Response (-3dB) | AUX(500mvV) Iw i{Hz~kHz;} 20~50 10~6)
11 | Tone Control, +10dB AUX 100Hz | 1Ww dB +10+2 +1041 |
[| | 10kHz 1W dB | +10+2 | +1021
: 12 |Subwoofer Out sub-vol +6dB [AUX(200mvV) | 1kHz | M-Vol Max Vv | 2+0.5 2+0.3
| 13 |Phono Equalization PHONO 100Hz | TAPE OUT dB RIAA+1.5 RIAA1
10kHz i dB | RIAA+1.5| RIAA+1
; 14 |Input Overload at 0.5% THD il MM 1kHz TAPE OUT mV >120 > 14¢
| 15 DIN Power at 1% THD AUX __tkHZ | R/O W > 135 > 14(
' 16 |Muting Level AUX(500mV); 1kHz R/O dB >60 >65
~@ REAR AMP SECTION
Measurements conditions : Input level 300mV, Rear level maz., Master volume adj. delay time 20ms
| NO DESCRIPTION INPUT FREQ. REMARK | UNIT LIMIT | NOMINAL
' 4 |Power Output 0.7% THD AUX | 1kHz | 80hms Ww >50 >52
"2 Total Harmonic Distortion AUX | _1kHz 1W % | <1 <0.7
_ 3 |SIN Ratio DOLBY AUX _| __R/O dB} 55 >63
‘THF-A Filter STADIUM AUX | : dB >55 | 263
! THEATER AUX i : dB >55 | >63
ose HALL AUX : dB >50 | 363
4 | Frequency Response AUX | 1kHz | 1W Hz~kHz,| 100~6 80~7
‘at+3dB
(ONLY
DOLBY)
|
AUX
|
;

« CENTER AMP SECTION
Measurements conditions : Input level 300mV, WIDE mode Center level max., Master volume adj.
NO DESCRIPTION | INPUT | FREQ. REMARK ! UNIT | LIMIT | NOMINAL |
' 1 |Power Output at 0.3% THD AUX | IkHz Bohms | W | _2130 > 132
2_|Total Harmonic Distortion AUX |__1kHz_ 1W % | <03 <0.2 |
3 ‘S/N Ratio, IHF-A Filter AUX | R/O dB >73 >78
4 |Frequency Response | |
IDOLBY MODE NORMAL AUX 1wW iHz~kHz) _120~20 | 100~30 |
WIDE AUX 1wW /Hz~kHz} 60~20 40~30 |
@ VIDEO SECTION
NO | DESCRIPTION "INPUT FREQ. REMARK | UNIT | LIMIT | NOMINAL |
| 1 |Output Level at 750hms | VCR1(1Vp-p)|_1MHz | Vp-p | 140.2) 1401 |
| 2 Frequency Response " 1MHz 'Hz~MHz DC~6 | DC~63 |
3 |S/N Ratio : 4MHz | dB | 40 | 45 |
4 |Crosstalk " 1MHz 7B 40 45. |
a AM SECTION
Measuring methods in confirmity with IEC standard 315
Measurements condition AM - MW
* Radio frequency = 1000/999kHz, Audio frequency = 400Hz
“LM: Radio frequency = 207kHz, Audio Frequency = 400Hz
* Reference level = 5 mV/m, 10 mV/m on 50 ohms
* Test point : MW TP1=594 kHz, TP2=999 kHz, TP3=1404 kHz (USA Version)
“ Test point : MW TP1=600 kHz, TP2=1000 kHz, TP3=1400 kHz (Europe Version)
* Test point : LW TP1=162 kHz, TP2=207 kHz, TP3=1404 kHz (USA Version)
* Test point : LW TP1=600 kHz, TP2=1000 kHz, TP3=1400 kHz (Europe Version)
NO) DESCRIPTION VERSION | UNIT; LIMIT | NOMINAL |
| 1 |Tuning Cover Range LOW~HIGH USA | kHz | §20~1710
| EUROPE | kHz | 522~1611
iSTEP USA si kHz 10
= EUROPE kHz __ 9
| 2 \Usable Sensitivity MW TP1 USA | uv/im , <800 |; <500
| TP2 uVim | <800 <500
i TP3 uvim | <800 = <500 |
| MW TP1 EUROPE uvVim <800 , <500 |
TP2 uV/m <800 <500 |
| TP3 uV/im | <800 <500 |
3 "SIN Ratio MW USA dB, 235 | >40
EUROPE dB >40 | >45
4 ‘Total Harmonic Distortion USA % <2 <1.0
| EUROPE % <1.5 <10 |
5 Over Load Distortion 5 mV_80 % MOD ty = 10 <5 |
6 (Frequency Response at - 6 dB MW | | Hz | 100~2K 80~2.2K |
7 |Selectivity 10 kHz/ 9 kHz MW | dB | 320 >25
| 8 AGC Figure of Merit dB | 550 355 |
| 9 ‘Image Rejection MW = TP3 i | dB} 330 335 |
| 10 |Whistle Modulation Input=1mV/m_ 21F | | % <15 — < 10 |
| 11 |Auto Stop Level MW uV/m_ | 800( + 6dB); 800( +5dB)
| 12 Tuned Level MW __uV/m_ | 800(+6dB) 800(+ 5dB),
_ 13 ‘Output Level mV 165+50 165+30 |

a FM SECTION
Measuring methods in confirmity with IEC standard 315
Measurements condition FM : Radio frequency = 98.1 MHz, Audio frequency = 1kHz
* Reference level = 1mV on ( 75 ohms, 300 ohms )
* Deviation : MONO = +75kHz, Stereo = +67.5kHz +7.5kHz (USA Version)
MONO = +40kHz, Stereo = +40kHz +7.5kHz (Europe Version)
* Test Point : TP 1 = 90.14MHz, TP2 = 98.1MHz, TP 3 = 106.1MHz
* Filter = B.P.F at STEREO
~NO: DESCRIPTION VERSION | UNIT LIMIT | NOMINAL |
|
1
Tuning
Renge
LOW~HIGH
|
USA
|
MHz
|
87.5
~
107.9
oa Europe | 87.5 ~ 108.0
‘Step AUTO/Man USA kHz ; 200
fo Europe 100/50
| 2 |Usable Sensitivity TP 1 i USA | GBF | <17.2 <14.2 |
SIN
=
30
dB
TP
2
|
dBf
;
<17.2
<14.2
|
TP 3 | | dBf <17.2 <14.2 |
‘S/N = 26 dB TP 1 Europe qBf |§ <202 (| <17.2
TP2 | dB | <20.2 <17.2
| TP 3 | =a dBf <20.2 <17.2
3
Full
Limiting
Sense
Output
=
-3
dB
|
USA
|
dBf
<152
|
<122
| Europe | dBf | <20.2 <17.2_|
| 4 ‘Auto Stop Level 2 dBf | 31.245 | 31.24+3 |
|
5
Auto
Error
USA
1
KHz
|
0
64200
|
425
1 | |___ Europe kHz +15 | +20
6 S/N Ratio MONO | dB >64 >68
| STEREO dB 260 | =64 |
|
7
‘Total
Harmonic
Distortion
MONO
%
<05
|
<O03
|
| STEREO | | % | <08 <O.5 |
_
8
'50
dB
Quietion
Sensitivity
MONO
|
USA
|
GBF
|
<23.2
|
<202
|
| STEREO | dBf § <48.3 | <453 |
46 dB Quietion Sensitivity MONO ___ Europe qBf = <232 <202 |
| STEREO | ___OBf <483 <453
| 9 |Channel Separation 100 H2z | | dB 235 i >40
—_ 1 kHz dB 6340, 345
oa 10 kHz | | dB | 230 | 235
10 |Frequency Response at +1.5 dB | I Hz 20~12.5 10~14
| 11 Spurious Response | USA | dB | 270 |, >80 |:
po 4 Europe | dB > 80: >90 |
| 12 |IF Rejection TP 1 | | 4B | =70 >80 |
| 13 Image Rejection TP 3 USA dB 386560) | «0365
a
___Europe
|
OB
|
=70
|
>80
|
| 14 :AM rejection Ratio | ; dB >50 i: 355 |
15 _ Capture Ratio {__ dB 22.5.) 22
|
46
.Alternative
CH
Selectivity
+400
kHz
|
dB
|
245
|
>860
' 17 ‘Output Level MONO | mV | 500+150 | 50+100 |
|
48
[RDS
Sensitivity
(Europe
|
dBf
|
<40.2
|
«382
|
w= GENERAL
Power
consumption
----------
rrr
rrr
crt
rte
r
rer
ctee
USA/Canada
:
4.5A,
Europe
1
100W
Power
Supplies
+--+
=s<se-ise
snes
e
neste
es
ee
Seite
reese
s
USA/Canada
:
AC
120V,
60Hz
Europe : AC 230v, 5OHz
Dimensions (WxHxD) -----++--0 rrr rrr rrr cre rrr retest cress 440 x 140x380 mm
17-5/16 x 5-1/2 x 14-1546 inchs
Weight (Net)- --------------2-e eer e rte rere eee renee! 15.9 kg (31.3 3 Ibs)

CIRCUIT DESCRIPTION
1C301 : CXP82840
1. Pin Description
GRID SEGMENT SEGMENT
NromwmDnwonrtrranr oo
SBE6SESSOGRRLHTHLSAKAAe See
LLEEEEE LET EILE LETT Ty
{oXOSOBLOTIOELOSIOAOSIO2O NOVES/BEE7(BEKB5)/041ESE216')
G7 O-— @0)—+O
GRID eae ae ae
NC O— (78)—+O
POWER DOWN O—+ 77)—+O
RDS CHECK O—+ (764) —+O
RDS START O—+(6) 75)—-O
ENCODER
UP
O—+(7)
?4)—+O
REMOTE O—+(8) 73—+O
ENCODER
DOWN
O—+(9)
?3—-O
NC O—(10) ?71)—+O
NC O—(11) (70)—+O
MAIN - MUTE O-«—(12) 69)—+-O
AMP DATA O=—(13) 68)—+O
AMP CLOCK O-—(14) 67)—-O
NC O—(15) CXP-82840 66)—+O
INt
O—+(6)
63—-O
kevin
|
N2
O-*G2
64)—-O
IN3 O—(18) 63)—+O
IN4 O—+(19) 62—-O
DIGI- LINK O--+(0) 61\—+O
MODEL-OPTION O—+(21) )
RDS
CLOCK
O-—(22)
69—-O
RDS
DATA
O-—(23)
G3)—+O
CENTER- MUTE O-—(24) 67)—+O
REAR MUTE O-—@5) 66)—+O
7001- DATA O«—(26) 65)—+O
7001- CLOCK O+—@7) 64)—+O
VREF O—@8) O
SLEEP O—+(29) 62)—+O
PROTECT
O—+(0)
6)—-O
ae eee: Pecueusee:
OomzZzana ZQr QoQoaqonanazauww
eeOnSee 2 2228858856
wwf OE uw Or 20Ra0
rs
c
xX
Oa
q
aa
Sy
>
QB
tw Ww o OF
Zu 0a - Oo
ae :
“”
=
fan}
=>
Yn
P19
P18
P17
P16
P15
P14
P13
P12
pir |
eo |e
P9 W
P8
P7
P6
P5
P4
P3
p2
Py
ST-BY RELAY
NC
TUNER MUTE
C7821 C.E
TC 9299 C.E
LM 7001 C.E
VCR2 F/R
AMP MUTE
NC
CINEMA BASS
4094A C.E

2. Input/Output Terminal Functions
G2/G1 Grid signal output for FIP.
POWER DOWN | Input for power down(Active low).
RDS CHECK Input for RDS check.
RDS START Input for RDS start.
ENC
UP/DOWN
|
Input
for
Encoder
up
and
down.
NC
REMOCON
Input
for
remote
control
signal.
(Active
low).
Puc
[hte
Output for main mute.
1/2
3
4
5
7/19
10/11
12 MAIN MUTE
Output is low level under the following conditions.
1. When power is turned on or off.
2. When function is changed.
3. When MONO or STEREO is changed.
4. When Low level is inputed to "PROTECTION" port of CPU.
5. When mute signal is received from the commander.
Output datasignal to MC14094, LC7821, LC7822 and TC9299.
Output clock signal to MC14094, LC7821, LC7822 and TC9299.
Input for selecting Model. ('L'>R525, 'H'R-725, AV725)
C-MUTE Output for center mute.
Output is low level under the following conditions.
1
1
2
2
2
3
4
15
0
1
2
23
24
1. When power is turned on or off.
2. When center mode is on or off.
3. When center mode is switched.

C-MUTE 4. When test tone mode is on or off, When the channels is changed
S-MUTE
the test tone mode.
5. When Low level is inputed to "PROTECTION" of CPU.
6. When mute signal is received from the commander.
24
5
2 Output for surround mute.
Output is low level under the following conditions.
1. When power is turned on or off.
2. When surround mode is on or off.
. When test tone mode is on or off, When the channels is changed
oo
the test tone mode.
. When delay time is changed.
5. When Low level is inputed to "PROTECTION" of CPU.
6. When mute signal is received from the commander.
26/27 | 7001-DATA/CLK | DATA/CLOCK Singnal output for LM7001.
AV REF Referance voltage of analog A/D converter.
2
2 SLEEP OPTION | Input for selecting function. ('H'—St-by, 'L'-Sleep.)
PROTECTION Signal input for protection wher low level is inputed, it ischinged to
STAND-BY mode.
STEREO Input for lighting the ST(Stereo), Inaicator(Active low).
S-METER Input signal level of tuner.
SUBWOOFER inplut for selecting subwoofer, when high level is inputed subwoofer volume
OPTION is operates.
35 STEP According to region, input for selecting the frequency bands and steps for
FM and AM
Settings are as follows
FREQUENCY BAND _—STEP
USA/ FM: 87.5 ~ 107.9 MHz 200 kHz
AM: 520 ~ 1710 kHz 10 kHz
EUROPE | FM: 87.5~108 MHz 50 kHz
aaa AM: 522 ~ 1611 kHz 9 kHz
KOREA FM: 87.5 ~ 107.9 MHz 200 kHz
eee AM: 522 ~ 1611 kHz 9 kHz
Input for selecting set. (65V--RDS Receiver, 2.5V—+Amp, 0V—Receiver)
Input for resetting CPU. (Active high)
39/40 Input/Output for cystal oscillator.
41 Ground.
8
AS)
30
31
32
33
34
36
37
38

nc [NetwesSC—“S*s*s*~“‘“S~*Ss*s—‘“—s~‘s~s~S~*Y
D
F
| == vDD | Power supply of CPU(+5V)
G
V ;
v
CE( :
E( ideo).
42
43
44
45
46/47
48
49
50
51
52
53
D
D
L
)
4
AMP-MUTE
When
the
power
is
on,
contro!
data
output
is
high
after
3
seconds.
nn
When the power is off, control data output is "L".
VCR2 OPTION Output signal for VCR2 Inputs. (‘H'-Front, 'L'-Rear)
CE(7001) LM7001 chip enable.
CE(9299) TC9299 chip enable. (Surr-Subwoofer Trim)
CE(7821 LC7821 chip enable. (Function select)
N
Output is high level under the following conditions.
1. When power is turned on or off.
2. When tuner band is changed.
3. When tuning up or down button is pressed.
4. When preset button is pressed.
5. When displayed preset number is changed during memory scan.
6. When Low lever is inputed to "PROTECTION" of CPU.
T-MUTE Output for tuner mute.
)
ST-BY Output for driving power relay. (Active high)
D
55
56
57
58
59
7. When mute signal is received from the commander.
61 vi
90-94 $28 - $32 Segment 28 - Segment 32
95-100 G8-G3 Grid 1 - Grid 5.

3. Block Diagram
@ XTAL
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z
CPU
CORE
SYSTEM
CONTROL|<>|
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|
@-@
GOIAG~G15/A15
Kis]
5
(3
|
' FOP z 2 Ks! PBO~PB7
@-@ Ate-A23 KB] CONTROLLER 5 al’! @-@
m~
|
t
as
PH7/A24~PD7/ASS K32_| g 3 :
Cr Eada Cea eee ee aes 4 RAM = yond
a
Pco/KRo~PC7/KR7 [8 3 | 32K / 40K BYTES 1536 BYTES |S} |
'
r
ey
a
PES/PWH oe-—| 14 BIT PWM GENERATOR |<>> m & CB poo-po7
1 ] @-
PE4/RMC o——| —
1 P| mote
eee
|
or
® eecee o> SERIAL i , rece
——
INTERFACE
|
FIFO
|
"O-
@rraneees So UNITO_! PRESCALER/ S2KHZ EL.
. ‘ TIME BASE TIMER | | TIMER /COUNTER SE @N! pro-pe7
@®)
PBE/SI1
Pinion
Mea
aren
eB
AB
ve
@
pp7/sot
—
SERIAL
INTERFACE
UNIT
4
|)
1
'
@-®@
@)
PBS/SCK1
(3
|
‘
'
yy
@® PEOANTO/ECO 8 BIT TIMER / COUNTER 0 Ky a oo
: 8 BIT TIMER 1 ; i
' '
@
SPENTO
oe
[46
BIT_
CAPTURE
kg
bes
Le
er
©
PELANT2ECI
TIMER
/
COUNTER
2
LI
|
BEI DS TTT ;
beer wee ee = ee ee ee ee ee
4. Key Matrix
Key Scan 2] Key Scan 3} Key Scan 4| Key Scan 5 | Key Scan 6 | Key Scan 7| Key Scan 8 | Key Scan 9| Key Scani0}Key Scan11
Pin 80 Pin 79 Pin 78 Pin 77 Pin 76 Pin 74
; F Station [Center Level Tuning Memory
ae 7 a | sain Pearse] owe [Tare [hemor | 7 | «| seo | semen | seen |
: : (Center Leve PTY FM Tuning i
F : Tape2, , Rear Level
F : Video Center Cinema Rear Level :
ree " au em | rie aie eau

ALIGNMENT PROCEDURES
TUNER
1. Equipment Required
« AM Standard Signal Generator (AM SSG) * Audio Generator
* Oscilloscope ¢ Distortion Meter
* AC Voltmeter - DC Voltmeter
* FM Standard Signal Generator (FM SSG) « Frequency Counter
* Stereo Modulator
Note : Disconnect external FM antenna prior to alignment.
2. Alignment
2-1. Alignment and Test Point
2-2. AM Alignment
Output of signa! generator should not be greater than necessary to obtain an optimum output reading.
- Signal generator modulation : 30 %
- RF signal frequency : 400 Hz
- Switch: Press the BAND button to AM
signal sa Equipment Adjustment
Step | Subject Generator Frequency Canneclioa Point Adjusi for
Frequenc Setting
Voltage (522kHz) (522kHz) to J22 (TP1) AM OSC(R)
2 RF 600kHz 600kHz 1) AC voltmeter and T1
Tuning (594kHz) (594kHz) oscilloscope to MW ANT(W Maximize
1400kHz speaker terminal TC1 audio outpy:
(1404kHz) (1404kHz) of L or R channel
* Feed signal should be fed to loop antenna through the test loop antenna 60 cm distant frem
the appliance.
* Repeat the step 1) and 2) until no further improvement occurs.
10

Maximize
audio output
IF 1000kHz 1000kHz Ac voltmeter and T3
(999kHz) (999kHz) oscilloscope to speaker [AM IFT
terminal of L or R channel
Tuned 1000kHz (999kHz) | 1000kHz "Tuned" flag in
Level 800 W/m (999kHz) the FL display
bel aca nl OE wl light on
3-3. FM Alignment
-
Output
of
signal
generator
should
not
be
greater
than
necessary
to
obtain
an
optimum
output
reading.
*
Signal
generator
deviation
:
USA/Canada/Korea
:
75kHz.
Europe
:
40kHz
*
RF
signal
frequency
:
1
kHz
Switch : Press the BAND button to FM and the FM MODE button to MONO
signal oe Equipment Adjustment
Step
|
Subject
Generator
Frequency
Canneetba
Point
Adjust
for
Frequenc Setting
HUBINS
98.1MHz
98.1MHz
DC
Volt
meter
Zero
reading
on
THD 98.1MHz 98. 1MHz Distortion meter to Minimize
of L or R channel
Tuned 98.1MHz (98MHz) | 98.1MHz VR2 “Tuned” flag in
Level
SSG
output
level
:
=p
the
FL
display
10
W/m
light
on
as 4. MPX Alignment
- Signal generator frequency : 98 MHz
* Signal generator deviation : USA: 75kHz. Europe : 40kHz
> RF signal frequency : 1 kHz
* Signal generator output level : 1000 .V/m
*
Connect
signal
generator
to
FM
antenna
terminal
through
FM
dummy
antenna
(75
&)
*
Switch
;:
Press
the
BAND
button
to
FM
and
the
FM
MODE
button
to
STEREO
19
kHz
Signal
Ndivaieat
Step.|
Subject
Modulation
Generator
Point
Adjust
for
Level
Setting
VR3
Set
AC
voltmeter
Seperation {8 % Modulation Pilot on
to 0 dB
Equipment
Connection
AC voltmeter to
speaker terminal
of R channel
AC voltmeter to AC voltmeter
speaker
terminal
reading
should
be
of
L
channel
at
least
40
dB
below
Pilot on AC voltmeter to
VR3 Set AC voltmeter
speaker terminal to 0 dB
of L channel
AC voltmeter to AC voltmeter
speaker
terminal
reading
should
be
of R channel at least 40 dB below
If
you
could
not
obtain
-40
dB
readings
in
steps
1
and
2,
readjust
VR3
until
you
obtain
-40
dB
readings.
Nominal
is
-45
dB.
(Europe:
Nominal
-42
dB,
Limit
-37
dB)
11

4. Equipment Connection
4-1. AM Alignment Connection
20" (60 cm)
|] TAPE OUT
JACK
Tuner
Front-End
(FE1)
* RDS VERSION : !C2
Loop Antenna
4-2. FM Dummy Antenna
125 @2 (112.5 Q)
Zin=752 () Zout = 3002
150 Q
FM Dummy Antenna to 30022 Antenna terminal of system.
4-3. FM RF/IF and MPX Alignment Connection
*DC
Voltmeter
FM Antenna Set
Terminal (3009) t | TAPEOUT
J j JACK
FM Dummy Tuner
Antenna Front-End
75Q
Stereo Audio
Modulator Generator
Distortion AC
Meter Voltmeter
12

TROUBLESHOOTING
Symptom Cause and Remedy
Receiver inoperative. A) Faulty AC power cord.
(FL indicator does not light.) Replace.
B) Defective the power switch.
Replace.
C) Broken wire in the power transformer.
Replace.
D) Blown fuse.
Replace the fuse.
A) Defective power transformer.
Replace.
B) Short on the primary or secondary of the transformer circuitry.
Repair the short.
C) Damaged rectifier D105-D112 or damaged transistor
Q215L/R/C/SL, Q216L/R/C/SL.
D) Short circuit in the amplifier circuit.
Repair the shorted component(s) in the amplifier circuit.
A) Defective in transistor Q215L/R, Q216L/R on the AMP302 Biard.
B) Pulled out of correct speaker swithch.
Fuse blows when power is turned on.
Power indicator lights but no sound from
both channels.
One channel does not work when volume
is at maximum with a test signal applied to
the center terminal of volume control of the
dead channe.
A) Defective in transistor Q215L/R or Q216L/R on the AMP302 Board.
Replace the defect.
B) Break in copper foil of printed circuit board.
Repair the defect.
C) Short in speaker output terminal.
Repair or replace.
A) Headphone plug does not match with jack.
Replace the jack.
B) Defective resistor R701U/R.
Replace.
A) Defective front-end (FE).
Replace.
B) Defective FM switch.
Replace the switch.
C) Defective transistor Q3 and ICS (IC2,IC3).
Replace the defective transistor or IC(s).
D) Defective coil T4, T5.
Replace the coil(s).
E) Defective lead-in.
Repair or replace the lead-in.
F) Ceramic filters CF 1, CF3 defective.
Replace the defective ceramic filter(s).
A) Improper adjustment.
Readjust VR3.
B) iC3 defective.
Replace.
C) Variable resistor VR3 defective.
Replace the variable resistor.
A) If volume from both L and R channels is not loud enough :
Front end section defective.
Faulty |C2, Coil T4 or T5.
If sound of one channel is not loud enough : Defective VR3.
Speaker works normally but headphones
inoperative.
FM inpoerative
Poor multiplex separation.
FM volume is insufficient.
13

Symptom
STEREO indicator does not light.
Cause and Remedy .
A) Defective indicator in FL.
Replace.
B) Improper adjustment of VR2 of tuner board.
Make readjustment.
C) Defective IC2.
Renlace the defective component.
FM Mono has no effect. A) Defective FM MODE switch.
Replace.
AM inoperative.
A) Damaged IC2 of tuner Board.
Replace.
B) Defective T1, T2, T3 or CF4 of Tuner Board.
Replace the defective component(s).
D) Defective varicap diodes VD1 or VD2.
Replace varicap diods(s).
E) Damaged AM loop antenna.
Repair or replace.
Bass control has no effect. A) Variable resistor BASS defective.
Replace.
Treble control has no effect.
Auto tune inpoerative. (UP/DOWN)
Manual tune inpoerative. (UP/DOWN)
(AM or FM)
Memory setting inpoerative.
FL inoperative.
Noisy volume control.
Remote Control Unit inoperative.
A) Variable resistor TREBLE defective.
A) Poor contact in Up/Down key.
Repair or replace.
B) Defective IC301.
Replace.
C) Defective tuner Circuit components.
Replace.
D) In case of FM only, improper adjustment of FM front-end.
Readjust.
A) Poor contact in Up/Down key.
B) Defective 1C301.
Replace.
A) Poor contact in memory keys 1-10.
Replace the defective component.
B) Defective 1C301.
Replace the defective component.
A) FL defective.
Replace.
B) Defective 1C301.
Replace.
C) Defective X-TAL 301.
Replace.
A) Defective volume.
Replace.
A) Weak battery.
Replace.
B) Defective.
Replace.
C) Defective IC301 (FRONT Board)
Replace. .
14

Ref. No
(1)
(1)
ayAvranrh wn
(8)
(9)
(9)
11
12
13
14
15
16
17
18
19
20
21/22
23/24
25
26
27/28
29
30-36
37
38
39
40
At
42
43
(43)
44
45
46
(46)
47
48
49
50
54
52
53
54
($4)
55
Description
PACKAGE
BOX CARTON
BOX CARTON
POLY BAG
FILM SOFT PE
CUSHION PLOY
ACCESSORIES
ANTENNA WIRE DIPOLE
ANTENNA LOOP
MATCHING TRANS
COMMANDER ASSY
BATTERY 1.5V AA (R6M)
MANUAL INSTRUCTION
MANUAL INSTRUCTION
MANUAL INSTRUCTION
CABINET & CHASSIS
PANEL FRONT
PANEL FRONT
PANEL FRONT
KNOB MAIN
KNOB ENCODER
KNOB ROTARY(A)
BADGE, Sherwood
LED GUIDE
CAP DECORATION
CAP DECORATION
WINDOW FL
WINDOW FL
BODY FRONT
BODY FRONT
BODY FRONT
JACK RCA, 3P
BRACKET JACK SWITCH
BUTTON PUSH
INDICATOR STANDBY
BUTTON STANDBY
BUTTON POWER
BUTTON POWER
HOLDER FL
SHIELD FENCE
CHASSIS FRONT
COVER BOTTOM
FOOT AL
FOOT PL
FRAME RIGHT
CUSHION FL B'D
HEATSINK, REG TR
HEATSINK, REG TR
HEATSINK, REG TR
FASTENER
SUPPORTER PCB
HEATSINK POWER
FRME LEFT
INSULATION COVER
AC OUTLET
AC OUTLET
AC OUTLET
JACK MULTI ROOM
JACK RCA, 3P
JACK RCA, 2P
JACK RCA, 3P
JACK RCA, 3P
JACK RCA, 9P
JACK RCA. 4P
JACK RCA, 6P
JACK RCA, 2P
JACK RCA, 6P
JACK RCA, 6P
ANTENNA TERMINAL
ANTENNA TERMINAL
JUMPER PLUG
MECHANICAL PARTS LIST
Part No.
6017040990160
6017040990190
6330040092010
6320040052010
6230042794010
£605010010000
E601010000000
L109284007100
830004025X010
G670001R50010
5707045950010
5707046390010
5707046390030
3067043468050
3067046128010
3067046138010
5087040768010
5087040778010
5097050641010
5637040591010
4350041551010
5127040931010
5127040931020
5077040063010
5077040073010
3417040721010
3417040721020
3417040731010
G606040300000
4010043616010
5090066821010
5160040643010
5090059231010
5090059071010
509005399101A
4320040841010
3070046576010
3210041046010
4310041996020
4007041021010
4000040201010
3200047716010
4050042265010
2120044338010
2120044358010
2120044338010
4420040323010
4420010153010
2120044958010
3200047706010
1240043892010
G435040070000
G435040110000
G435000160010
G402042070000
G606300395020
G601200900020
G606300390020
G606300390020
G607901500010
G602400910010
G603600920020
G601200440020
G603600920040
G603600920020
G590040470000
G59004046000A
L063040750000
Q'ty Version
enw awa a
ea a an = = =»
Meaaersanwnnn enn nn nnn nnn nN NN ae nNNnNANNAP BANA B BAN oO Bann nn nnn ninwan inna
D/RDS
A
D/RDS
AIK
RDS
AIK
D/RDS
AIK
OD/RDS
AIK
RDS
AIK
D/RDS
A
D/RDS
K
A
A/D/RDS
K
AIK
D/RDS
15
Ref. No Description Part No. Q'ty Version
56 HOLDER PCB 4320044751010 1
57 TERMINAL SPEAKER, 4P G61204030000B 1
58 TERMINAL SPEAKER, 2P G611040310000 1
59 TERMINAL SPEAKER, 8P G614081036000 1
60 BUSHING TERMINAL 2410040270010 14 D/RDS
61 GROUND TERMINAL 3790000090000 1
62 CHASSIS BACK 3207042746010 1 K
(62) CHASSIS BACK 3207042746020 1 A
(62) CHASSIS BACK 3207053166010 1 D
(62) CHASSIS BACK 3207042746050 1 RDS
63 STOPPER CORD 4380040162010 1
64 CORD AC POWER L061041210010 1 A
65 CORD AC POWER L061040421040 1 D/RDS
(65) CORD AC POWER L061041220010 1 K
66 COVER TOP 3000045396010 1 AIK
(66) COVER TOP 3000045406050 1 D/RDS
67 BRACKET PCB 4010056216010 1
68 JACK PHONE (G) G402040161330 1
69 HOLDER FAN 4320044706010 1
70 DC-BRUSHLESS FAN G720040030020 1
71 CLAMPE WIRE 4330040213010 2
72 FELT BUFFER 4050045669010 1 AIK
swi SWITCH POWER Go000041610000 1 D/RDS
SW2/SW3 SWITCH PUSH G000041170000 2
SW4 SWITCH TACT G180040500010 1 AIK
SW5-SW21 SWITCH TACT G180040500010 17
SW22-SW26 SWITCH TACT G180040500010 5 RDS
SW27 SWITCH TACT G180040500010 1 AIK
SW28-SW43 SWITCH TACT G180040500010 16
VR1 VOULME MAIN C495145300010 1
VR2 VOULME BLANCE C450042050000 1
VR3/VR4 VOULME BASS/TREBLE C450042060000 2
VR5 VOULME ENCODER C450042030010 1
HARDWARE KIT
$1/S2 SCREW #2FTC 3 x 8B BO10530083F10 2
$3-S55 SCREW #BTT 3 x 8B B020030083B10 53
$56-S69 SCREW #B WPTT 3 x 6Y BO20030061W10 14
$70-S79 SCREW #2 BTT 3x 8B B020030083B10 10
$80-S104 SCREW HEATSINK 1507041146010 25
$105 SCREW GUIDE(A) 1507041456010 1
$106/S107 SCREW GUIDE(B) 1507041446010 2
$108-S112 SCREW #B BTT 3x 8B B020030083B10 5
$113 SCREW GROUND 1507040996010 1
$114-S134 SCREW #B BTT 3x 8B B020030083B10 18
$132 SCREW GROUND 1507040996010 1
$133-S140 SCREW #B BTT 3 x 8B B020030083B10 8
$141-S144 SCREW GROUND 1507040996010 4
$145-S148 SCREW WSAM 4 x 8B BO20940083W10 4
$149-S154 SCREW BSAM 4 x 8B B020940083B10 6
$155-S157 SCREW #B BTT 3 x 8B B020030083B10 3
MISCELLANEOUS
POWER TRANS, 230/50 8200281016870 1 D/RDS
POWER TRANS, 120/60 8200281012670 1 A
POWER TRANS, 220/60 8200281012770 1 K
SPONGE RUBBER 4050045095010 1
CARD CABLE L301186213590 1
* Parts with blank version are available in common.
PRODUCT SAFETY NOTICE
Each precaution in this manual should be followed during servicing.
Components identified with the IEC symbol 4s in the parts list are of
special significance to safety. When replacing a component
identified with A. , use only the replacement parts designated, or
parts with the same ratings of resistance, wattage or voltage that
are designated in the parts list in this manual. Leakage-current or
resistance measurements must be made to determine that exposed
parts are acceptably insulated from the supply circuit before
returning the product to the customer.

EXPLODED VIEW
Model No. : R-725/RDS - AV-725
$155/156
|
i <o
a
Sy
a
Seis
PCB7
(SP
oN
r
is
(SPK
S/W)
<>
By
@
4 PCB8 (VCR2 FRONT)
16 17

Bites
Bak se
i
18
c1O7L
c108L
PRINTED CIRCUIT BOARDS
PCB2 (MAIN)
cs03 cs505
Lijelsisisist7ieteies
IKOREA ss [NB1A 250VI
EVROPE.ETC|TIA 250V
19
Model No. : R-725/RDS - AV-725
MAIN B’D

Model No. : R-725/RDS - AV-725
PCB5 (FRONT)
WD 1V-04
CN304
PCB8 (VCR2 FRONT) VCR2 SELECT B’D
PCB7 (SPK SWITCH)
sans
scupoetseaccorameety mene
J. a
7 PCB6 (TONE) — “TGRUTESTROOT TE Re SELECT
ALU 1V-0A VcR2 FRONT BD
fences eye
c6o02L
SW-2 B’D SW-1 B’D
20 21

AV-725
725/RDS R Model No
PCB4 (AMP 202)
a
a =
7
é
R240SL
PCB3 (AMP 302)
#2804137
‘D CNT-2B
(sae) G0zO #
ovty
4
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N
22