Yamaha A-S701 User manual

SERVICE MANUAL
INTEGRATED AMPLIFIER
A-S701
■CONTENTS
TO SERVICE PERSONNEL........................................... 2
IMPEDANCE SELECTOR.............................................. 3
FRONT PANELS ............................................................ 3
REAR PANELS .......................................................... 4–5
REMOTE CONTROL PANEL......................................... 6
SPECIFICATIONS...................................................... 6–7
INTERNAL VIEW ........................................................... 8
SERVICE PRECAUTIONS ............................................. 8
DISASSEMBLY PROCEDURES...............................9–11
UPDATING FIRMWARE......................................... 12–14
SELF-DIAGNOSTIC FUNCTION ........................... 15–25
POWER AMPLIFIER ADJUSTMENT..................... 26–27
IC DATA.................................................................. 28–30
PIN CONNECTION DIAGRAMS .................................. 31
BLOCK DIAGRAM ....................................................... 33
WIRING DIAGRAMS.................................................... 34
PRINTED CIRCUIT BOARDS................................ 35–51
SCHEMATIC DIAGRAMS ...................................... 53–59
REPLACEMENT PARTS LIST............................... 61–75
REMOTE CONTROL.................................................... 76
1 0 1 3 1 4
'14.12
IP
A-S701

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A-S701
■TO SERVICE PERSONNEL
1. Critical Components Information
Components having special characteristics are marked ⚠and
must be replaced with parts having specifications equal to
those originally installed.
2. Leakage Current Measurement (For 120V Models Only)
When service has been completed, it is imperative to verify
that all exposed conductive surfaces are properly insulated
from supply circuits.
• Meterimpedanceshouldbeequivalentto1500ohmsshunted
by0.15μF.
WALL
OUTLET
EQUIPMENT
UNDER TEST
AC LEAKAGE
TESTER OR
EQUIVALENT
INSULATING
TABLE
• Leakagecurrentmustnotexceed0.5mA.
• BesuretotestforleakagewiththeACpluginbothpolarities.
For U model
“CAUTION”
“F1: FORCONTINUEDPROTECTIONAGAINSTRISKOFFIRE,REPLACEONLYWITHSAMETYPE8A,
125VFUSE.”
For C model
CAUTION
F1: REPLACEWITHSAMETYPE8A,125VFUSE.
ATTENTION
F1: UTILISERUNFUSIBLEDERECHANGEDEMÉMETYPEDE8A,125V.
WARNING: CHEMICAL CONTENT NOTICE!
This product contains chemicals known to the State of California to cause cancer, or birth defects or other reproductive
harm.
DO NOT PLACE SOLDER, ELECTRICAL/ELECTRONIC OR PLASTIC COMPONENTSIN YOUR MOUTHFOR ANYREASON
WHATSOEVER!
Avoid prolonged, unprotected contact between solder and your skin! When soldering, do not inhale solder fumes or
expose eyes to solder/flux vapor!
If you come in contact with solder or components located inside the enclosure of this product, wash your hands before
handling food.
About lead free solder
All of the P.C.B.s installed in this unit and solder joints are soldered using the lead free solder.
Among some types of lead free solder currently available, it is recommended to use one of the following types for the
repair work.
•Sn + Ag + Cu (tin + silver + copper)
•Sn + Cu (tin + copper)
•Sn + Zn + Bi (tin + zinc + bismuth)
Caution:
As the melting point temperature of the lead free solder is about 30°C to 40°C (50°F to 70°F) higher than that of the lead
solder, be sure to use a soldering iron suitable to each solder.

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■IMPEDANCE SELECTOR
IMPEDANCE SELECTOR
WARNING:
Do not change the setting of the IMPEDANCE SELECTOR
switch when the unit power is switched on, as doing so may
damage the unit.
■FRONT PANEL
A-S701

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A-S701
■REAR PANELS
A-S701 (U model)
A-S701 (R model)
A-S701 (A model)

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A-S701
A-S701 (B, G models)
A-S701 (L model)

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A-S701
■SPECIFICATIONS
■Audio Section
Minimum RMS Output Power (Power Amp. Section)
(20 Hz to 20 kHz)
8ohms, 0.019 % THD................................................ 100 W + 100 W
6 ohms, 0.038% THD................................................ 120 W + 120 W
Dynamic Power Per Channel (IHF)
8/ 6 / 4 / 2 ohms ............................................140 / 170 / 220 / 290 W
MAX Power Per Channel (1 kHz) [B,Gmodels]
0.7 % THD, 4 ohms...................................................................160 W
IEC Power (1 kHz) [B,Gmodels]
0.019 % THD, 8ohms...............................................................115W
Power Band Width
0.04%THD,50W,8ohms.................................... 10Hzto50kHz
Damping Factor (SPEAKER-A)
1 kHz, 8ohms..................................................................240 or more
Maximum Effective Output Power (JEITA)
(1 kHz, 10 % THD)
R,Lmodels(8ohms)........................................................145Wh
R model (6 ohms)..............................................................170 Wh
Input Sensitivity/Input Impedance
PHONO(MM) ...................................................... 3.0mV/47k-ohms
CD, etc. .............................................................. 200mV/47k-ohms
Maximum Input Signal (1kHz)
PHONO (MM) (0.03 % THD)........................................45mV or more
CD, etc. (0.5% THD).....................................................2.2 V or more
Output Level/Output Impedance
REC OUT .............................................. 200 mV / 1.0 k-ohms or less
Subwoofer OUT ..................................................... 3.5V / 1.2 k-ohms
(Cut off Frequency: 100 Hz)
Headphone Jack Rated Output/Impedance
CD, etc. (Input, 1 kHz, 200 mV, 8ohms) ............. 470 mV / 470 ohms
Frequency Response
CD, etc. (20 Hz to 20 kHz) ............................................... 0 ±0.5dB
CD, etc. Pure DIRECT ON (10 Hz to 100 kHz) ................0 ±1.0 dB
RIAA Equalization Deviation
PHONO (MM) ...................................................................... ±0.5dB
Total Harmonic Distortion (20Hzto20kHz)
PHONO (MM) to REC OUT (2.5V) ............................. 0.03 % or less
CD,etc.toSPOUT(50W,8ohms)........................... 0.019 % or less
Signal to Noise Ratio (IHF-ANetwork)
PHONO (MM) (5mV Input shorted) ........................... 82 dBor more
CD, etc. (Pure DIRECT ON) (200 mV input shorted)... 99dBormore
CD DIRECT ON ........................................................ 104 dBor more
Residual Noise(IHF-ANetwork)
................................................................................................ 40 μV
■REMOTE CONTROL PANEL
RAS14

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•DIMENSIONS
Channel Separation
CD, etc. (Input 5.1 k-ohms shorted)
1kHz......................................................................... 65dBormore
10 kHz....................................................................... 50dBormore
Tone Control Characteristics
BASS
Boost/Cut(20Hz)................................................................ ±10dB
Turnover frequency ...............................................................400Hz
TREBLE
Boost/Cut(20kHz)............................................................... ±10dB
Turnover frequency ..............................................................3.5kHz
Continuous Loudness Control
Attenuation (1 kHz) .................................................................. -30 dB
Supported Digital Audio Format (COAXIAL / OPTICAL) /
PCM (2-ch) ..............................192 / 176.4 / 96 / 88.2 / 48/ 44.1 kHz
PCM Word Depth
............................................................................................ 16 / 24 bit
Gain Tracking Error
(0 to -99 dB)..................................................................0.5dBor less
■General
Power Supply
U model ....................................................................AC 120 V, 60 Hz
R model ........................................ AC 110–120/220–240 V, 50/60 Hz
Amodel ....................................................................AC 240 V
, 50 Hz
B, Gmodels.............................................................. AC 230 V, 50 Hz
L model........................................................ AC 220–240 V, 50/60 Hz
Power Consumption
U, R, A, B, Gmodels ................................................................270 W
L model.....................................................................................230 W
Standby Power Consumption
...................................................................................................0.5W
Maximum Power Consumption [Rmodel]
1 kHz, 6 ohms, 10 % THD........................................................580W
Dimensions (W x H x D)
....................................... 435x 151 x 387 mm (17-1/8" x 6" x 15-1/4")
Weight
...............................................................................11.2 kg (24.7 lbs.)
Finish
..................................................................... Black color / Silver color
Accessories
Remote control .............................................................................. x 1
Battery(R6,AA,UM-3)................................................................. x 2
Power cable (2 m) ......................................................................... x 1
* Specifications are subject to change without notice.
U............................ U.S.A. and
Canadian models
R.................... General model
T.....................Chinese model
K ......................Korean model
A .................Australian model
B.......................British model
G................. European model
L................. Singapore model
J...................Japanese model
Top view
Unit: mm (inch)
単位：mm（インチ）
335 (13-1/4")50
(2")
20.5
(3/4")
25.5 (1")
387 (15-1/4")
341 (13-3/8")
55
(2-1/8")
46 (1-3/4")
240 (9-1/2")
ø 60
Front view
435 (17-1/8")
151 (5-7/8")
130 (5-1/8")
21
(7/8")

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A-S701
■INTERNAL VIEW
■SERVICE PRECAUTIONS
Safety measures
•Some internal parts in this product contain high voltages and are dangerous. Be sure to take safety measures during
servicing, such as wearing insulating gloves.
•Note that the capacitors indicated below are dangerous even after the power is turned off because an electric charge
remains and a high voltage continues to exist there.
Before starting any repair work, connect a discharging resistor (5k-ohms/10 W) to the terminals of each capacitor
indicated below to discharge electricity.
The time required for discharging is about 30 seconds per each.
C134, C135on MAIN (1) P.C.B.
For details, refer to “PRINTED CIRCUIT BOARDS: MAIN (1) P.C.B.”.
a
MAIN (8)
b
MAIN (2)
c
FUNCTION (4)
d
MAIN (3) (R model)
e
DIGITAL
f
MAIN (6)
g
FUNCTION (1)
h
FUNCTION (2)
i
FUNCTION (3)
j
MAIN (5)
k
MAIN (1)
l
MAIN (4)
m
POWER TRANSFORMER
n
OPERATION (7)
o
OPERATION (4)
p
OPERATION (3)
q
OPERATION (1)
r
OPERATION (2)
s
OPERATION (6)
t
OPERATION (5)
Top view
Front view
1 3 8 92
n o p q r
4 5 6 7
st
k jlm

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■DISASSEMBLY PROCEDURES
(Remove parts in the order as numbered.)
Disconnect the power cable from the AC outlet.
1. Removal of Top Cover
a. Remove 4 screws (1), 4 screws (2) and screw (3). (Fig. 1)
b. Remove the top cover. (Fig. 1)
2. Removal of Front Panel Unit
a. Remove screw ( ④), screw ( ⑤) and then remove the top frame.(Fig. 1)
b. Pull out the knobs and cap. (Fig. 1)
c. Remove 7 screws ( ⑦). (Fig. 1)
d. Remove the front panel unit. (Fig. 1)
Fig. 1
Front panel unit
Knob VOLUME
Knob INPUT
Knob BASS/TREBLE/BAL./LOUD.
Knob SPEAKERS OFF/A/B/A+B
Cap POWER
⑦
⑦
Top frame
①
④
⑤
Top cover
①
②
③

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⑩
Sub-chassis unit
Hook CB706
CB101
CB105
Hook CB853
⑧
⑧
CB2
CB21
FUNCTION (1) P.C.B.
FUNCTION (2) P.C.B.
FUNCTION (3) P.C.B.
CB506
CB505
DIGITAL P.C.B.
⑫
⑬
CB508
CB304
CB301
CB303
⑪ ⑨
3. Removal of Sub-chassis Unit
a. Remove 2 screws ( ⑧). (Fig. 2)
b. Remove CB505, CB508, CB706 and CB853. (Fig. 2)
c.
Release 2 hooks and then remove the sub-chassis unit. (Fig. 2)
4. Removal of DIGITAL P.C.B.
a. Remove 3 screws (9). (Fig. 3)
b. Remove 3 screws (j). (Fig. 2)
c.
Remove CB21, CB301, CB303 and CB304 and then remove the DIGITAL P.C.B . (Fig. 2)
5. Removal of DIGITAL P.C.B.
a. Remove 7 screws (k). (Fig. 3)
b. Remove screw (l) and screw (m). (Fig. 2)
c.
Remove CB2, CB101, CB105and CB404 and then remove the FUNCTION (1)–(3) P.C.B . (Fig. 2)
Fig. 2
Fig. 3

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When checking the P.C.B.s:
•Put the rubber sheet and the cloth over this unit, Then place the sub-chassis unit on the cloth and check it. (Fig. 4)
•Connect the ground point of the sub-chassis unit to the chassis with a ground lead or the like. (Fig. 4)
•Reconnect all cables (connectors) that have been disconnected.
•When connecting the flexible flat cable, be careful with polarity.
Ground lead
Sub-chassis unit
Rubber sheet and cloth
Fig. 4

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■UPDATING FIRMWARE
When the following parts are replaced, the firmware must be updated to the latest version.
FUNCTION P.C.B.
●Confirmation of firmware version
Before and after updating the firmware, check the firmware version by using the self-diagnostic function menu.
Start up the self-diagnostic function, have the firmware version indicated, and note them down.
(For details, refer to “SELF-DIAGNOSTIC FUNCTION”)
* When the firmware version is different from written one after updating, perform the updating procedure again from
the beginning.
●Factory preset
After updating the firmware, revert to factory presets with the following procedure to properly store the setup
information.
Start up the self-diagnostic function.
(For details, refer to “SELF-DIAGNOSTIC FUNCTION”)
Set the “SPEAKERS”selector to the “A”position, press the “z”(power) switch to turn off the power once and press the
“z”(power) switch to turn on the power again.
Then the factory preset is performed.
●Required Tools
•CD, DVD or BD player (with DIGITAL OUTPUT (OPTICAL or COAXIAL) jack)
•Optical cable (when OPTICAL jack is used)
•Digital audio pin cable
(when COAXIAL jack is used)
•Firmware CD
Download the latest firmware from the specified download source and create the firmware CD.
* The following models can be used as a tool to update the firmware.
CD player: CD-C600/CD-S1000/CD-S2000/CD-S300/CD-S700/CDX-496/CDX-596/CDX-890
DVD player: DV-C6760/DVD-840/DVD-C740/DVD-C750/DVD-C940/DVD-C950/DVD-CX1/DVD-S1200/
DVD-S1800/DVD-S2300(MKII)/DVD-S2700/DVD-S30/DVD-S510/DVD-S520/DVD-S530/
DVD-S540/DVD-S550/DVD-S657/DVD-S700/DVD-S80/DVD-S840
BD (Blu-ray) player: BD-940/BD-S1065/BD-S1900/BD-S2900/BD-S671
Others: CDR-D651/CDR-HD100

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●Connection
Use the optical cable (when OPTICAL jack is used) or Digital audio pin cable (when COAXIAL jack is used) to connect
the CD, DVD or BD player and the unit.
●Operation Procedures
1. Set this unit to the firmware update mode.
a. Connect the power cable of this unit to the AC outlet. (Fig.1)
b. Set the “z”(power) switch to the OFF position. (Fig.1)
c. Fully turn the “BALANCE”knob to the right (R). (Fig.1)
d. Fully turn the “VOLUME”knob to the left (minimum). (Fig.1)
e While pressing the “PURE DIRECT”switch, press the “z”(power) switch to turn on this unit. (Fig.1)
The unit is set to the firmware update mode.
When this unit is set to the firmware update mode, the power indicator flashes at a 1-second interval.
When this unit is set to the firmware update mode
, the “ LINE3 ” indicator light up. (Fig. 2)
2. Play the firmware CD on the CD/DVD/BD player. Updating of the firmware starts automatically. (Fig. 3)
Note:
•Ifthelightingpatternofthe“INPUT”indicatorsdoesnotchange10secondsormoreafterplaybackofthe
firmware CD was started, try updating the firmware again, starting from the beginning of the procedure.
•Becarefulthatthepowercableisnotunpluggedandthepowervoltagedoesnotdropwhilethermwareisbeing
updated. Otherwise, firmware updating may fail and cannot be performed again.
Updating started Updating
Fig. 3
"PURE DIRECT" switch
"VOLUME" knob
"BALANCE" knob
Power indicator
" " (Power) switch
OFF ON/
STANDBY
Fig. 1
Fig. 2
Power cable
AC outlet

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3. After the firmware has been updated, all “INPUT”indicators light up. (Fig. 4)
After checking that all “INPUT”indicators light up, press the “z”(power) switch to turn it off, then on again.
Note:
If the power indicator flashes at a 0.5-second interval or all “INPUT”indicators do not light up after updating the
firmware, try updating the firmware again, starting from the beginning of the procedure. (Fig. 5)
These indicate that the data was not correctly written to the microprocessor. If the same result is obtained after trying
to update the firmware again, the microprocessor may be damaged.
4. Press the “z”(power) switch to turn off the power.
5. Eject the firmware CD from the CD/DVD/BD player.
6. Start up the self-diagnostic function and check that the firmware version is the same as written one.
(For details, refer to “Indication of firmware version”.)
7. Revert to factory presets.
(For details, refer to “Factory Preset”.)
Fig. 5
Update is completed
Fig. 4

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■SELF-DIAGNOSTIC FUNCTION
This unit has self-diagnostic functions that provides the following functions.
•Indication of firmware version
•Indication of “AUTO POWER STANDBY”switch status
•Indication and checking of protection information
•Factory preset
●Starting Self-Diagnostic Function
1. Press the “z”(power) switch to turn off this unit. (Fig.1)
2. Connect the power cable of this unit to the AC outlet. (Fig.1)
3. Set the “SPEAKERS”knob to the “OFF”position. (Fig.1)
Note: Since factory preset is reserved by turning off this unit when the “SPEAKERS”knob is set to the “A”position, set
the “SPEAKERS”knob to the “OFF”position before starting the self-diagnostic function mode
.
4. Set the “BASS”, “TREBLE”and “BALANCE”knobs to the top positions. (Fig.1)
Note:
Be sure to set the “BASS”, “TREBLE”and “BALANCE”knobs to the top positions. These positions are stored when the
self-diagnostic function mode is started, and software corrections are made to the top position for each selector.
In addition, the self diagnostic function mode cannot be started if the top positions for the knobs are off by more than
±5% of the 2.5V input voltage.
5. Set the “LOUDNESS”knob to the “FLAT”position. (Fig.1)
6. Press the “z”(power) key to turn on this unit. (Fig.1)
7. Press the “z”(AMP) key on the remote control to set this unit to standby. (Fig.2)
8. Repeat pressing the “PURE DIRECT”key 6 times within 15seconds. (Fig.1)
9. Press the “z”(AMP) key on the remote control to turn on this unit. (Fig.2)
This unit starts the self-diagnostic function mode.
Keys of this unit Key on Remote control
“PURE DIRECT”key
“BASS”, “TREBLE”, “BALANCE”knobs “LOUDNESS”knob
“” (Power) switch “SPEAKERS”knob
“” (AMP) key
Power cable
AC outlet
Fig. 1 Fig. 2

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●Display provided when Self-Diagnostic Function started
●Details of Indication
•Indication of firmware version
The firmware version of the microprocessor (IC502 of the FUNCTION P.C.B.) is indicated in the binary code (BCD) using
the “COAXIAL”, “CD”, “TUNER”and “PHONO”indicators. (Fig.4)
•Indication of AUTO POWER STANDBY switch status
The status (ON/OFF) of the “AUTO POWER STANDBY”switch located on the rear panel is indicated using the “LINE 2
INPUT”indicator. (Fig. 5)
Light up :“AUTO POWER STANDBY”switch is “ON”
Off: “AUTO POWER STANDBY”switch is “OFF”
Fig. 5
・Indication of firmware version
・Indication of auto power standby status
・Indication of protection information
Power indicator
INPUT indicators
Fig. 3
INPUT indicators Firmware version
Binary number (BCD) [Lightup: 1, Off: 0]
Decimal number
COAXIAL CD TUNER PHONO
(2 = 8)
3(2 = 4) 2(2 = 2)
1(2 = 1) 0
0 V0010 (8+2=10)
V0011 (8+2+1=11)
V0012 (8+4=12)
101
1101
0011
•
•
•
•
•
•
Fig. 4

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•Indication of protection information
The protection information is indicated by the flashing pattern of the “z”(power) indicator.
PS (Power Supply) protection
Cause: The voltage in the power supply section is abnormal.
Normal value: 2.559 to 3.259V (AD value: 130-167)
Detection port: PRV (FUNCTION (1) P.C.B. 93 pin of the microprocessor IC502)
Detected at: ACL, ±15, +5S
I protection L/Rch
Cause: Excess current flow into amplifier.
Speaker terminal shorted. (*)
Normal value: LOW (0V)
Detection port: PRI (FUNCTION (1) P.C.B. 69 pin of the microprocessor IC502)
Detected at: PRI (Amplifier output L/Rch of MAIN (1) P.C.B.)
* If the protection function works due to shortage at the speaker terminal, the power turns off at the excess current
protection L/Rch.
However, pressing the “z”(power) switch for OFF/ON, all “INPUT”indicators flash 5times and the power to turn on.
DC voltage protection
Cause: Abnormal DC voltage of amplifier output.
Normal value: 0.947 to 2.517V (AD value: 48-129)
Detection port: PRD (FUNCTION (1) P.C.B. 89 pin of the microprocessor IC502)
Detected at: Amplifier output L/Rch of MAIN (1) P.C.B.
USB OC (Over Current) protection
Cause: USB power supply is overcurrent.
Normal value: HIGH (5V)
Detection port: USB_N_OCPRT（FUNCTION (1) P.C.B. 45pin of the microprocessor IC502）
Detected at: USB_OCPRT (IC309 of DIGITAL P.C.B.)
THM protection L/Rch
Cause: Abnormal temperature of heat sink.
Normal value:
A-S501: 0.20 to 1.80V (AD value: 10-91)
A-S301: 0.20 to 1.66V (AD value: 10-85)
Detection port: THM1 (FUNCTION (1) P.C.B. 84 pin of the microprocessor IC502)
THM2 (FUNCTION (1) P.C.B. 83 pin of the microprocessor IC502)
Detected at:
THML (Heat sink temperature detection Lch IC101 of the MAIN (4) P.C.B.)
THMR (Heat sink temperature detection Rch IC102 of the MAIN (5) P.C.B.)
Power indicator flashing pattern
Flashing 2 /
Flashing 3 /
Flashing 4 /
Flashing 6 /
Flashing 7 /
Lit up/
: Lit
: Off
500mS 500mS 500mS 1000mS 500mS 500mS 500mS 500mS
Continuous
Types of protection function /
PS protection /

I protection L/R ch /
DC protection /

THM protection L/R ch /
Diode THM protection /
No protection function /
Flashing 5 /
USB OC protection /
(U,R,A,B,G,L models)

1000mS
1000mS
500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS
500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS
500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS
500mS 500mS 500mS 500mS
500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS 500mS
1000mS
1000mS
1000mS
500mS 1000mS
500mS 500mS 500mS 500mS 500mS
Fig. 6

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Diode THM protection
Cause: Abnormal temperature of diode (D111 of MAIN (1) P.C.B).
Normal value: 0 to 0.346V (AD value: 0-18)
Detection port: THM3 (FUNCTION (1) P.C.B. 97 pin of the microprocessor IC502)
Detected at: THM3 (TH501 of FUNCTION (4) P.C.B., D111 of MAIN (1) P.C.B.)
•Checking of protection information
Check the following information when a protection function has been activated.
・Protection history (up to 4)
・Position of “VOLUME”knob when the protection function was activated (*)
・AD value when the protection function was activated
・AD value when the diode THM protection function was activated
・Operating information for the speaker relay/headphones relay
・AD value for the “BALANCE”knob
・Input source information
* Since the “VOLUME”knob automatically moves to the position when the protection function was activated, do not
to operate any other knob while the “VOLUME”knob is moving.
If several protection functions have been activated, history for up to four of the most recent protection functions can be
viewed by turning the knob indicated below.
BASS:History for the most recent protection function
TREBLE: History for the 2nd most recent protection function
BALANCE: History for the 3rd most recent protection function
LOUDNESS:History for the 4th most recent protection function
* When the “BASS”or “TREBLE”knob is turned to “–”or the “BALANCE”knob is turned to “L”, the corresponding protection history will
be indicated by the power indicator.
* When the “LOUDNESS”knob is turned to a position halfway between “FLAT”and “-30dB”, the 4th most recent protection history will be
indicated.
* When the “BASS”, “TREBLE”and “BALANCE”knobs are set to their top positions and the “LOUDNESS”knob is set to “FLAT”, the most
recent protection function (the same as that indicated by turning the “BASS”knob) is indicated by the “z”(power) indicator. However,
the “VOLUME”knob will not move at this time. The “VOLUME”knob will move if a protection history is selected with one of the knobs.
(Fig. 7)
* The order of priority for indicating the protection history is as follows:
BASS > TREBLE > BALANCE > LOUDNESS.
If the “TREBLE”and “BALANCE”knobs were turned at the same time, the “TREBLE”knob will have priority, and the 2nd most recent
protection function is indicated.
When the 4th most recent protection function is indicated
Fig. 7
Note:
When checking the protection history, the “VOLUME”
knob will automatically move to the position when
the protection function was activated. Do not operate
any other knob while the “VOLUME”knob is moving.
* When the “LOUDNESS”knob is turned to a
position halfway between “FLAT”and “-30dB”,
the 4th most recent protection history will be
indicated.

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Example:
To check the history for the 3rd most recent protection function, set the “SPEAKERS”knob to “OFF”, the “BASS”and “TREBLE”
knobs to their top positions, the “LOUDNESS”knob to “FLAT”, and the “BALANCE”knob to “L”. (Fig. 8)
1. AD value when the protection function was activated
At the same time that the protection history is indicated, the AD value when the protection function was activated is
indicated in binary code (BCD) using the “INPUT”indicators. (Fig. 9)
BASS:
AD value for the most recent protection function
TREBLE:
AD value for the 2nd most recent protection function
BALANCE:
AD value for the 3rd most recent protection function
LOUDNESS:
AD value for the 4th most recent protection function
* When checking the AD value when the protection function was activated, the “VOLUME”knob will automatically
move to the position when the protection function was activated. Do not operate any knob while this knob is moving.
* For functions If protection L/Rch or USB over current protection or if there is no protection history, all “INPUT”
indicators will be off since there are no AD values stored.
Fig. 8
Fig. 9
Indication example
“INPUT”indicators
AD valueBinary number (BCD) [Light up: 1, Off: 0]
LINE 3 LINE 2 LINE 1 OPTICAL COAXIAL CD TUNER PHONO
27= 128 26= 64 25= 32 24= 16 23= 8 22= 4 21= 2 20=1 5V=255
0 0 0 0 0 0 0 0 0 /255
0 1 0 0 0 0 0 0 64 /255
1 0 0 0 0 0 0 0 128 /255
1 0 1 0 1 0 0 0 168 /255
1 1 1 1 1 1 1 1 255 /255
Indications for AD values of the abnormal voltage detected when a protection function is activated
Fig. 10

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2. AD value for diode THM (temperature)
Turn the “TREBLE”knob to “+”and the “SPEAKERS”knob to “OFF”. (Fig. 11)
The AD value for the diode THM (temperature) (TH501 on FUNCTION (4) P.C.B. and D111 on MAIN (1) P.C.B.) is indicated
in binary code (BCD) using the “INPUT”indicators. (Fig. 11)
* The AD value of the diode (D111 on MAIN (1) P.C.B.) temperature when a protection function is activated is stored,
regardless of the type of protection function.
3. Operating information for the speaker relay/headphones relay
Turn the “TREBLE”knob to “+”and the “SPEAKERS”knob to “A”. (Fig. 13)
The ON/OFF states of speaker relays A/B(RY101 and RY102 on MAIN (1) P.C.B.) and the headphones relay (RY103 on
MAIN (1) P.C.B.) when a protection function is activated are indicated using the “INPUT”indicators. (Fig.13)
Note:
Since factory preset is reserved by turning off this unit when the “SPEAKERS”knob is set to the “A”position, be sure to set
the “SPEAKERS”knob to the “OFF”position before turning off this unit in case of keeping setup information stored in the
backup memory of the microprocessor.
“INPUT”indicators
AD valueBinary number (BCD) [Light up: 1, Off: 0]
LINE 3 LINE 2 LINE 1 OPTICAL COAXIAL CD TUNER PHONO
27= 128 26= 64 25= 32 24= 16 23= 8 22= 4 21= 2 20=1 5V=255
0 0 0 0 0 0 0 0 0 /255
0 0 1 0 1 0 0 0 40 /255
0 1 0 0 0 0 0 0 64 /255
1 0 0 0 0 0 0 0 128 /255
1 0 1 0 1 0 0 0 168 /255
1 1 1 1 1 1 1 1 255 /255
Fig. 12
Fig. 11
Indication example
Fig. 13
Indication example “CD”Indicator：Headphones relay ON/OFF
“TUNER”Indicator：Speaker relay B ON/OFF
“PHONO”Indicator：Speaker relay A ON/OFF
Example:
“CD”indicator lights up: Headphones relay is ON
“TUNER”indicator off: Speaker relay B is OFF
“PHONO”indicator off: Speaker relay A is OFF
* The state indicated in the example shows that headphones are plugged into the PHONES
jack and both speaker outputs A and B are off.