Sony EA-80 User manual

1st Edition
EDUCATIONAL AMPLIFIER
EA-80
SERVICE MANUAL

The material contained in this manual consists of
information that is the property of Sony Corporation and is
intended solely for use by the purchasers of the equipment
described in this manual.
Sony Corporation expressly prohibits the duplication of any
portion of this manual or the use thereof for any purpose
other than the operation or maintenance of the equipment
described in this manual without the express written
permission of Sony Corporation.
Le matériel contenu dans ce manuel consiste en infor-
mations qui sont la propriété de Sony Corporation et sont
destinées exclusivement à l’usage des acquéreurs de
l’équipement décrit dans ce manuel.
Sony Corporation interdit formellement la copie de quel-que
partie que ce soit de ce manuel ou son emploi pour tout
autre but que des opérations ou entretiens de l’équipement
à moins d’une permission écrite de Sony Corporation.
Das in dieser Anleitung enthaltene Material besteht aus
informationen, die Eigentum der Sony Corporation sind,
und ausschließlich zum Gebrauch durch den Käufer der in
dieser Anleitung beschriebenen Ausrüstung bestimmt sind.
Die Sony Corporation untersagt ausdrücklich die Ver-
vielfältigung jeglicher Teile dieser Anleitung oder den
Gebrauch derselben für irgendeinen anderen Zweck als die
Bedienung oder Wartung der in dieser Anleitung
beschriebenen Ausrüstung ohne ausdrückliche schrift-liche
Erlaubnis der Sony Corporation.
!WARNING
This manual is intended for qualified service personnel
only.
To reduce the risk of electric shock, fire or injury, do not
perform any servicing other than that contained in the
operatinginstructionsunlessyouarequalifiedtodoso.
Refer all servicing to qualified service personnel.

1
EA-80
TABLE OF CONTENTS
1. OPERATING INSTRUCTIONS
2. SERVICE OVERVIEW
2-1. LOCATION OF PRINTED CIRCUIT BOARDS ......................................... 2-1
2-2. NOTE ON INSTALLING COVER ............................................................... 2-1
2-3. CONNECTOR SPECIFICATION ................................................................. 2-2
2-4. PERFORMANCE CHECK MODE ............................................................... 2-3
2-4-1. Switch, Indicators and Audio Circuit Check .......................................... 2-3
2-4-2. Switch, Indicators, Audio and Communication Circuit Check
by an Oscilloscope.................................................................................. 2-4
2-4-3. Indicators, Audio and Communication Circuits
Check by EA-80 Connected to LLC-8000 ............................................. 2-4
2-5. NOTES ON REPAIR PARTS........................................................................ 2-5
2-5-1. Notes on Repair Parts ............................................................................. 2-5
2-5-2. Replacement of Chip Parts ..................................................................... 2-5
3. SPARE PARTS
3-1. NOTES ON REPAIR PARTS........................................................................ 3-1
3-2. EXPLODED VIEW ....................................................................................... 3-2
3-3. ELECTRICAL PARTS LIST......................................................................... 3-3
3-4. SUPPLIED ACCESSORIES.......................................................................... 3-4
4. SEMICONDUCTOR PIN ASSIGNMENTS
DIODE............................................................................................................ 4-1
TRANSISTOR ............................................................................................... 4-1
LED ................................................................................................................ 4-1
IC .................................................................................................................... 4-1
5. BLOCK DIAGRAM
6. BOARD LAYOUTS AND SCHEMATIC DIAGRAM
SW-952........................................................................................................... 6-1
AU-254 ........................................................................................................... 6-2

1-1
EA-80
SECTION 1
OPERATING INSTRUCTIONS
Operating the EA-80 Educational Amplifier
Make copies of this page and hand out a copy to each
student, if necessary.
This indicator is lit after
ATTENDANCE is
pressed.
However, it will begin
to blink if you call the
instructor by pressing
the CALL button.
RESPONSE
indicators
During analyzer test,
these indicators blink.
12345
RESPONSE
CALL
VOLUME
ATTENDANCE
EDUCATIONAL AMPLIFIER EA-80
Signing in
Press ATTENDANCE when instructed to do so by your instructor.
Note
You cannot sign out on your unit once you have signed in.
You can, however, use this button as a CALL button after you have signed in.
Calling the instructor
Press CALL.
The instructor will answer your call.
Adjusting the sound
volume
Rotate VOLUME until the
optimum sound volume is
obtained.
Put on the
headset
with the
microphone
to the left.
Position
the microphone close
to your mouth.
Headset
Taking an analyzer test
1 Listen to the question.
After the RESPONSE indicators begin to blink, you can start responding.
2 Press the RESPONSE button (1 to 5) that corresponds to what you think is the correct answer.
Only the RESPONSE indicator corresponding to the pressed button keeps blinking and remaining
RESPONSE indicators go off.
To change your answer:
Press another button. The blinking RESPONSE indicator goes off and the RESPONSE indicator
corresponding to the button just pressed starts blinking.
As long as the RESPONSE indicator corresponding to the pressed button is blinking, you can continue
changing your answer.
When the blinking RESPONSE indicator corresponding to the pressed button lights
The instructor has closed the test. You cannot respond or make further changes.
3 Check the correct answer.
The instructor presses the button of the correct answer on the control unit.
The RESPONSE indicator corresponding to the correct answer blinks rapidly. When your answer is
correct, the RESPONSE indicator corresponding to the pressed button blinks rapidly. When your answer
is wrong, the RESPONSE indicator of your answer remains lit.
Chapter 1 Outline
1-14 Chapter 1 Outline
This section is extracted from page 1-14 in LLC-8000 operation manual. (part number : 3-858-846-13)

2-1
EA-80
SECTION 2
SERVICE OVERVIEW
2-1. LOCATION OF PRINTED CIRCUIT
BOARDS
1
2
1SW-952 BOARD : Switch & CPU
2AU-254 BOARD : Audio
2-2. NOTE ON INSTALLING COVER
When installing the cover, put the harness in the notch of
the AU-254 board so that the cover does not catch the
harness.
Cover
AU-254
Board
Harness
Notch

2-2 EA-80
2-3. CONNECTOR SPECIFICATION
2
13
4
5
7
8
6
DIN 8P (type b)
<TOP VIEW> CN1/AU-254 Board
Pin No. Signal name Function/Specification Input/Output
1 P.GND *1 GND for +15V —
2 A.GND *1 GND for Audio —
3 PGM -10 dB Input
4 D.SIG Digital Signal 2400bps Input/Output
5 MONI -10 dB *2 Output
6 COLD GND for D.SIG —
7+15V +15 V D.C Power Input
8 INCOM -10 dB Input
0 dB =0.775 Vrms
CN3/AU-254 Board
Pin No. Signal name Function/Specification Input/Output
1 AUX L IN -10 dB Input
2 AUX R IN -10 dB Input
3 A.GND GND for Audio —
4 PGM OUT -10 dB Output
5 MIC OUT -10 dB Output
6 A.GND GND for Audio —
0 dB =0.775 Vrms
6
1
ILG Connector 6P
<TOP VIEW>
+
G
7
1
2
CN1
+15 V
Power
Supply
*1: Connecting a power supply to EA-80, short pin 1 of CN1 to pin 2 of CN1.
*2:The level of the signal supplied from AUX L IN or AUX R IN is -16 dB.
EA-80

2-3
EA-80
2-4. PERFORMANCE CHECK MODE
2-4-1. Switch, Indicators and Audio Circuit
Check
1. Connect the pin 7 of the 8P connector (CN1) on the
AU-254 board to the +terminal of a power supply, and
the pins 1 and 2 of CN1 on the AU-254 board to GND
of the power supply.
Use the modified RK-8XXX cable, shown below, to
facilitate the check required.
2. Set a DC out voltage to +15 V, and turn on the power
switch.
3. Keep pressing the switches SW1, 3 and 5 on on the
SW-952 board until completing step 5 below.
The SW1, 3 and 5 on the SW-952 board is the 1, 3 and
5 buttons on the display, respectively.
4. Keep pressing the switch SW6 on on the SW-952
board, that is, the ATTENDANCE/CALL button until
completing step 5 below.
5. Three seconds later, all response indicators (D1 through
D6 on the SW-952 board) flash.
6. Release the SW1, SW3, SW5 and SW6.
7. (a) Switches and indicators check
Every pressing the following switches turn the
indicator shown in the table to on and off.
Switch Indicator
Reference No. Display Reference No. Display
SW1 1 D1 1
SW2 2 D2 2
SW3 3 D3 3
SW4 4 D4 4
SW5 5 D5 5
SW6 CALL/ D6 CALL /
ATTENDANCE ATTENDANCE
(b) Audio circuit check
• While the D1 lights, a transistor (Q2) is off. While the
D1 does not light, the Q2 is on.
(When the Q2 is on, it does not supply the sound of
HS-MIC to HS-PHONE(L) and HS-PHONE(R).)
(Refer to Block Diagram in Section 5.)
• While the D2 lights, a transistor (Q1) is off. While the
D2 does not light, the Q1 is on.
(When the Q1 is on, it does not supply the sound of
PGM to HS-PHONE(L) and HS-PHONE(R).) (Refer
to Block Diagram in Section 5.)
RED +15V
GND
D. SIG
PGM
INCOM
MONI
RED
BLU
WHT
BLK
BRW
YEL
Shield
Shield
(not connected)
Board
RK-8XXX

2-4 EA-80
2-4-2. Switch, Indicators, Audio and
Communication Circuit Check by an
Oscilloscope
1. Connect the pin 7 of CN1 on the AU-254 board to the +
terminal of the power supply, and the pins 1 and 2 of
CN1 to GND of the power supply.
Use the modified RK-8XXX cable to facilitate the
check required. (Refer to step1 in 2-4-1. Switch,
Indicators and Audio Circuit Check.)
2. Connect the pin 4 of CN1 on the AU-254 board to
GND of the power supply.
3. Set a DC out voltage to +15 V, and turn on the power
switch.
4. Two seconds later, all response indicators (D1 through
D6 on the SW-952 board) flash.
5. Disconnect the pin 4 of CN1 on the AU-254 board
from GND of the power supply.
6. With transmitting “55H” code from the pin 3 of IC1
(TxD terminal) on the SW-952 board, all response
indicators light.
With all response indicators flashing, that is, without
lighting, it is abnormal. Check the signals between the
pin 1 of IC1, the pin 3 of IC1 and the pin 4 of CN1 on
the AU-254 board.
7. (a) Switches and indicators check
Perform the same step as step 7(a) in 2-4-1. Switch,
Indicators and Audio Circuit Check.
(b) Audio circuit check
Perform the same step as step 7(b) in 2-4-1. Switch,
Indicators and Audio Circuit Check.
(c) Communication circuit check
Using an oscilloscope, confirm that “55H” code is
transmitted to the pin 4 of CN1. With transmitting
“55H” code to the pin 4 of CN1, it shows the following
waveform on the oscilloscope.
b6 bØ
110101
55
0.42 msec H
0
TXD TERMINAL
"55 H"
Start bit
Stop bit
2-4-3. Indicators, Audio and Communication
Circuits Check by EA-80 connected to
LLC-8000
1. Press the POWER switch on the LLC-8000 to turn the
total LLC-8000 system on.
(Do not press the ATTEND button on the LLC-8000.
Not pressing the ATTEND button does not light the
indicator located at the left-above the monitor button on
the LLC-8000.)
2. Check switches, indicators and audio circuit by the
same steps as steps 3 through 7 in 2-4-1. Switch,
Indicators and Audio Circuit Check.
3. Communication circuit check.
When the communication is established, the indicator
that shows the student unit, EA-80, being checked and
located at the left-above the monitor button on the
LLC-8000, lights.
4. Press the POWER switch on the LLC-8000 to turn the
system off.

2-5
EA-80
2-5. NOTES ON REPAIR PARTS
2-5-1. Notes on Repair Parts
(1) Safety Related Components Warning
Components marked !are critical to safe operation.
Therefore, specified parts should be used in the case of
replacement.
(2) Standardization of Parts
Repair parts supplied from Sony Parts Center may not
be always identical with the parts which actually in use
due to “accommodating the improved parts and/or
engineering changes” or “standardization of genuine
parts”.
This manual's exploded views and electrical spare parts
list are indicating the part numbers of “the standardized
genuine parts at present”.
(3) Stock of Parts
Parts marked with “o” SP (Supply Code) column of the
spare parts list are not normally required for routine
service work. Orders for parts marked with “o” will be
processed, but allow for additional delivery time.
(4) Units for Capacitors, Inductors and Resistors
The following units are assumed in schematic diagrams,
electrical parts list and exploded views unless otherwise
specified.
Capacitors : µF
Inductors : µH
Resistors : Z
2-5-2. Replacement of Chip Parts
Required Tools
Soldering iron: 20 W
If possible, use a soldering-iron tip
heatcontroller set to 270 ±10 ˚C.
Braided wire : Solder Taul or equivalent
Sony part No. 7-641-300-81
Solder : 0.6 mm dia. is recommended.
Tweezers
Soldering Conditions
Soldering iron temperature: 270 ±10 ˚C
Soldering time : Less than 2 seconds
per pin
Replacement of Resistor and Capacitor
1. Place the soldering-iron tip onto the chip part and heat it
up until the solder is melted. When the solder is melted,
slide the chip part aside.
2. Make sure that there is no pattern peeling, damage and/
or bridge around the desoldering position.
3. After removing the chip part, presolder the area, in which
the new chip part is to be placed, with a thin layer of solder.
4. Place new chip part in the desired position and solder
both ends.
NOTE Do not use a chip part again once it has been removed.
Replacement of Transistors and Diodes
1. Cut the terminals of the chip part with nippers.
2. Remove the cut leads with soldering iron as above.
3. Make sure that there is no pattern peeling, damage and/
or bridge around the desoldering positions.
4. After removing the chip part, presolder the area, in which
the new chip part is to be placed, with a thin layer of solder.
5. Place new chip part in the desired position and solder the
terminals.
Replacement of ICs
1. Using the braided wire, “SOLDER TAUL” (Sony Part No.
7-641-300-81), remove the solder around the pins of the
IC-chip to be removed.
2. While heating up the pins, remove the pins one by one
using sharp-pointed tweezers.
3. Make sure that there is no pattern peeling, damage and/
or bridge around the desoldering position.
4. After removing the chip part, presolder the area, in which
the new chip part is to be placed, with a thin layer of
solder.
5. Place new chip part in the desired position and solder the
pins.
Terminals Terminals Terminals
Terminal
Capacitor Resistor Transistor, Diode
Nipper
Transistor

3-1
EA-80
SECTION 3
SPARE PARTS
3-1. NOTES ON REPAIR PARTS
(1) Safety Related Components Warning
Components marked !are critical to safe operation.
Therefore, specified parts should be used in the case of
replacement.
(2) Standardization of Parts
Repair parts supplied from Sony Parts Center may not
be always identical with the parts which actually in use
due to “accommodating the improved parts and/or
engineering changes” or “standardization of genuine
parts”.
This manual’s exploded views and electrical spare parts
list are indicating the part numbers of “the standardized
genuine parts at present” .
(3) Stock of Parts
Parts marked with “o” SP (Supply Code) column of the
spare parts list are not normally required for routine
service work. Orders for parts marked with “o” will be
processed, but allow for additional delivery time.
(4) Units for Capacitors, Inductors and Resistors
The following units are assumed in schematic diagrams,
electrical parts list and exploded views unless otherwise
specified.
Capacitors : µF
Inductors : µH
Resistors : Z

3-2 EA-80
No. Part No. SP Description
1 A-8316-825-A o MOUNTED CIRCUIT BOARD, AU-254
*Includes SW-952 board.
2 X-3167-999-1 o PANEL ASSY
3 1-506-705-11 o CONNECTOR, POST HEADER, ILG (6P)
4 1-561-320-41 s DIN SOCKET 8P
5 1-572-404-11 s SWITCH, PUSH (1 KEY)
6 1-573-798-11 s JACK, MINIATURE (DIA. 3.5)
7 1-958-213-11 o HARNESS, SUB (1)
8 3-165-013-11 o KEY (S), TOP
9 3-747-922-21 s KNOB
10 4-937-336-32 o HOLDER, LED (h=4 mm)
*for D1 through D5
11 4-937-336-91 o HOLDER, LED (h=6 mm)
*for D6
12 8-719-064-85 s DIODE TLOU114
13 8-759-495-61 o IC TMP90PH-EA80V100
3-2. EXPLODED VIEW
1
4
63
7
2
8
513 5
11
10 9
12
8
PS 3x6PS 3x6
PTP3x8PTP3x8

3-3
EA-80
------------
AU-254 BOARD (AU-254 BOARD)
------------
Ref. No. Ref. No.
or Q'ty Part No. SP Description or Q'ty Part No. SP Description
1pc A-8316-825-A o MOUNTED CIRCUIT BOARD, AU-254 R8 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
AU-254 mounted circuit board includes SW-952 mounted circuit R9 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
board. R10 1-216-093-00 s METAL, CHIP 68k 5% 1/10W
R11 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
C1 1-126-786-11 s ELECT 47uF 20% 16V R12 1-216-021-00 s METAL, CHIP 68 5% 1/10W
C2 1-126-791-11 s ELECT 10uF 20% 35V R13 1-216-105-91 s METAL, CHIP 220k 5% 1/10W
C3 1-163-239-11 s CERAMIC, CHIP 33pF 5% 50V R14 1-216-081-00 s METAL, CHIP 22k 5% 1/10W
C4 1-163-038-91 s CERAMIC 0.1uF 25V R15 1-216-105-91 s METAL, CHIP 220k 5% 1/10W
C5 1-126-786-11 s ELECT 47uF 20% 16V R16 1-216-105-91 s METAL, CHIP 220k 5% 1/10W
C6 1-163-251-11 s CERAMIC, CHIP 100pF 5% 50V R17 1-216-081-00 s METAL, CHIP 22k 5% 1/10W
C7 1-164-346-11 s CERAMIC 1uF 16V R18 1-216-105-91 s METAL, CHIP 220k 5% 1/10W
C8 1-164-346-11 s CERAMIC 1uF 16V R19 1-216-073-00 s METAL, CHIP 10k 5% 1/10W
C9 1-163-239-11 s CERAMIC, CHIP 33pF 5% 50V R20 1-216-105-91 s METAL, CHIP 220k 5% 1/10W
C10 1-164-346-11 s CERAMIC 1uF 16V R21 1-216-025-91 s METAL, CHIP 100 5% 1/10W
C11 1-164-346-11 s CERAMIC 1uF 16V R22 1-216-105-91 s METAL, CHIP 220k 5% 1/10W
C12 1-163-239-11 s CERAMIC, CHIP 33pF 5% 50V R23 1-216-021-00 s METAL, CHIP 68 5% 1/10W
C13 1-163-038-91 s CERAMIC 0.1uF 25V R24 1-216-073-00 s METAL, CHIP 10k 5% 1/10W
C14 1-126-786-11 s ELECT 47uF 20% 16V R25 1-216-105-91 s METAL, CHIP 220k 5% 1/10W
C15 1-126-786-11 s ELECT 47uF 20% 16V R26 1-216-105-91 s METAL, CHIP 220k 5% 1/10W
C16 1-163-239-11 s CERAMIC, CHIP 33pF 5% 50V R27 1-216-021-00 s METAL, CHIP 68 5% 1/10W
C17 1-126-786-11 s ELECT 47uF 20% 16V R28 1-216-081-00 s METAL, CHIP 22k 5% 1/10W
C18 1-164-346-11 s CERAMIC 1uF 16V R29 1-216-081-00 s METAL, CHIP 22k 5% 1/10W
C19 1-164-346-11 s CERAMIC 1uF 16V R30 1-216-049-91 s METAL, CHIP 1k 5% 1/10W
C20 1-164-346-11 s CERAMIC 1uF 16V R31 1-216-049-91 s METAL, CHIP 1k 5% 1/10W
C21 1-126-786-11 s ELECT 47uF 20% 16V R32 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
C22 1-163-038-91 s CERAMIC 0.1uF 25V R33 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
C23 1-163-038-91 s CERAMIC 0.1uF 25V R34 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
C24 1-126-786-11 s ELECT 47uF 20% 16V *R35 1-215-866-11 s METAL 330 5% 1W
C25 1-164-346-11 s CERAMIC 1uF 16V *Board suffix number -11 only
C26 1-163-251-11 s CERAMIC, CHIP 100pF 5% 50V
*R35 1-247-744-11 s CARBON 270 5% 1/2W
C27 1-164-346-11 s CERAMIC 1uF 16V *Board suffix number -12 and higher
C28 1-164-346-11 s CERAMIC 1uF 16V
C29 1-126-791-11 s ELECT 10uF 20% 35V R36 1-216-021-00 s METAL, CHIP 68 5% 1/10W
C30 1-126-791-11 s ELECT 10uF 20% 35V R37 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
*C100-109 1-163-005-11 s CERAMIC, CHIP 470pF 10% 50V R38 1-216-073-00 s METAL, CHIP 10k 5% 1/10W
*Board suffix number -12 and higher R39 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
R40 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
CN1 1-561-320-41 s CONNECTOR, DIN 8P, FEMALE
CN2 1-958-213-11 o HARNESS, SUB (1) R41 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
CN3 1-506-705-11 o CONNECTOR, ILG 6P, MALE R42 1-216-033-00 s METAL, CHIP 220 5% 1/10W
*R100-102 1-216-049-91 s METAL, CHIP 1k 5% 1/10W
D1 8-719-109-85 s DIODE RD5.1ES-B2 *Board suffix number -12 and higher
D2 8-719-157-97 s DIODE RD3.6SB
D3 8-719-157-97 s DIODE RD3.6SB
IC1 8-759-745-64 s IC NJM4560M
IC2 8-759-745-64 s IC NJM4560M
IC3 8-759-745-64 s IC NJM4560M
J1 1-573-798-11 s JACK, MINIATURE (3.5mm)
J2 1-573-798-11 s JACK, MINIATURE (3.5mm)
Q1 8-729-027-55 s TRANSISTOR DTC143EKA-T146
Q2 8-729-027-55 s TRANSISTOR DTC143EKA-T146
R1 1-216-057-00 s METAL, CHIP 2.2k 5% 1/10W
R2 1-216-081-00 s METAL, CHIP 22k 5% 1/10W
R3 1-216-073-00 s METAL, CHIP 10k 5% 1/10W
R4 1-216-049-91 s METAL, CHIP 1k 5% 1/10W
R5 1-216-033-00 s METAL, CHIP 220 5% 1/10W
R6 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
R7 1-216-093-00 s METAL, CHIP 68k 5% 1/10W
3-3. ELECTRICAL PARTS LIST

3-4 EA-80
------------
SW-952 BOARD
------------ Ref. No.
Ref. No. or Q'ty Part No. SP Description
or Q'ty Part No. SP Description
4pcs 7-621-843-45 s SCREW, WOOD +R 3.1x16
All component parts on the SW-952 board is supplied
together with ordering the AU-254 mounted circuit board.
1pc 4-937-336-91 o HOLDER, LED
5pcs 4-937-336-32 o HOLDER, LED
*C1 1-115-871-11 s ELECT 1uF 20% 50V
*Board suffix number -11 only
*C1 1-126-794-11 s ELECT 4.7uF 20% 50V
*Board suffix number -12 and higher
C3 1-126-786-11 s ELECT 47uF 20% 16V
CNI1 1-526-662-21 o SOCKET, IC (DP) 40P
D1 8-719-064-85 s LED TLOU114, ORANGE
D2 8-719-064-85 s LED TLOU114, ORANGE
D3 8-719-064-85 s LED TLOU114, ORANGE
D4 8-719-064-85 s LED TLOU114, ORANGE
D5 8-719-064-85 s LED TLOU114, ORANGE
D6 8-719-064-85 s LED TLOU114, ORANGE
D7 8-719-991-75 s DIODE RB425D
IC1 8-759-495-61 o IC TMP90PH-EA80V100
R1 1-216-073-00 s METAL, CHIP 10k 5% 1/10W
R2 1-216-073-00 s METAL, CHIP 10k 5% 1/10W
R3 1-216-073-00 s METAL, CHIP 10k 5% 1/10W
R4 1-216-073-00 s METAL, CHIP 10k 5% 1/10W
R5 1-216-073-00 s METAL, CHIP 10k 5% 1/10W
R6 1-216-073-00 s METAL, CHIP 10k 5% 1/10W
R7 1-216-057-00 s METAL, CHIP 2.2k 5% 1/10W
R8 1-216-057-00 s METAL, CHIP 2.2k 5% 1/10W
R9 1-216-057-00 s METAL, CHIP 2.2k 5% 1/10W
R10 1-216-057-00 s METAL, CHIP 2.2k 5% 1/10W
R11 1-216-057-00 s METAL, CHIP 2.2k 5% 1/10W
R12 1-216-055-00 s METAL, CHIP 1.8k 5% 1/10W
R13 1-216-041-00 s METAL, CHIP 470 5% 1/10W
R14 1-216-057-00 s METAL, CHIP 2.2k 5% 1/10W
R15 1-216-057-00 s METAL, CHIP 2.2k 5% 1/10W
R16 1-216-051-00 s METAL, CHIP 1.2k 5% 1/10W
R17 1-216-063-91 s METAL, CHIP 3.9k 5% 1/10W
R18 1-216-101-00 s METAL, CHIP 150k 5% 1/10W
R19 1-216-083-00 s METAL, CHIP 27k 5% 1/10W
RV1 1-241-358-11 s RES, ADJ, CARBON 20k
SW1 1-572-404-11 s SWITCH, PUSH
SW2 1-572-404-11 s SWITCH, PUSH
SW3 1-572-404-11 s SWITCH, PUSH
SW4 1-572-404-11 s SWITCH, PUSH
SW5 1-572-404-11 s SWITCH, PUSH
SW6 1-572-404-11 s SWITCH, PUSH
X1 1-579-929-11 s RESONATOR, CERAMIC 9.8300MHz
3-4. SUPPLIED ACCESSORIES

4-1
EA-80
IC
Semiconductors of which functions are equivalent are described here. For parts replacement, refer to the section of Spare Parts in this
manual. The circuit diagram of each IC is obtained from the IC data book published by the manufacturer.
SECTION 4
SEMICONDUCTOR PIN ASSIGNMENTS
DIODE, TRANSISTOR, LED, IC
R1
R2
—TOP VIEW—
—TOP VIEW—
—TOP VIEW—
DIODE
TRANSISTOR LED
DTC143EKA-T146
(R1=4.7 K, R2=4.7 K)
RB425D
RB425D-T146 RD3.6SB RD3.6SB-T1
RD5.1ES-B2
RD5.1ESB
TLOU114 ; ORANGE
IC
1

2

3

4
8

7

6

5
V EE
V CC
TYPE V CC 

+2 to +16V

+2 to +18V
+3 to +20V
+5 to +12V
+5 to +22.5V
+2.5 to +18V
+1 to +3.5V
+2 to +20V
+5 to +16V
062/072/082/4556A/
M5218/BA15218/
33178/34182 TYPES
4580 TYPE
5532 TYPE
CXA1297 TYPE
M5219/M5220 TYPES
MC33077DR2
NJM2100 TYPE
OP-297 TYPE
OTHERS
V EE 

_2 to _16V

_2 to _18V
_3 to _20V
_5 to _12V
_5 to _22.5V
_2.5 to _18V
_1 to _3.5V
_2 to _20V
_5 to _16V
_ +
+ _
DUAL OPERATIONAL AMPLIFIERS
(DUAL-SUPPLY TYPE)
—TOP VIEW—
NJM4560M (JRC)FLAT PACKAGE
NJM4560M-TE2

4-2 EA-80
IC
1
3
4
5
6
7
8
9
10
11
12
13
14
17
18
19
20
15
16
239
40
37
38
35
36
33
34
32
30
31
29
28
27
26
25
24
23
22
21
C-MOS 8 BIT MICRO CONTROLLER
—TOP VIEW—
(RxD) P31
(TxD) P33
(SCLK) P32 P27 (A15)
P26 (A14)
P25 (A13)
P24 (A12)
P23 (A11)
P22 (A10)
P21 (A9)
P20 (A8)
P17 (A7)
P16 (A6)
P15 (A5)
P14 (A4)
P13 (A3)
P12 (A2)
P11 (A1)
P10 (A0)
X2
X1
(
RD
) P35
(
WR
) P36
(TO1/
WAIT
) P37
NMI
EA
CLK
(D0) P00
(D1) P01
(D2) P02
(D3) P03
(D4) P04
(D5) P05
(D6) P06
(D7) P07
V
SS
(GND)
(INT0) P80
(INT1/TI2) P81
RESET
(
RD
) P35
(
WR
) P36
12 (D0) P00
(D1) P01
(D2) P02
(D3) P03
(D4) P04
(D5) P05
(D6) P06
(D7) P07
P27 (A15)
P26 (A14)
P25 (A13)
P24 (A12)
P23 (A11)
P22 (A10)
P21 (A9)
P20 (A8)
P17 (A7)
P16 (A6)
P15 (A5)
P14 (A4)
P13 (A3)
P12 (A2)
P11 (A1)
P10 (A0)
X1
X2
CLK
(INT0) P80
(INT1/TI2) P81
(TO1/
WAIT
) P37
(RXD) P31
(SCLK) P32
(TxD) P33
13
14
15
16
17
18
19
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
21
22
11
4
5
10
23
7
9
8
6
1
2
3
NMI
EA
RESET
V CC
(+5 V)
INPUT/OUTPUT
INPUT
P00 - P07/(D0 - D7)
P10 - P17/(A0 - A7)
P20 - P27/(A8 - A15)
; PROGRAM MEMORY DATA PORT 0
; PROGRAM MEMORY ADDRESS PORT 1
; PROGRAM MEMORY ADDRESS PORT 2
EA
; EXTERNAL ACCESS
NMI
; NON-MASCABLE INTERRUPT
RESET
; RESET
X1 ; CRYSTAL OSC 1
P31/R
X D; PORT31/SERIAL RECEIVE DATA
P80/INT0 ; PORT80/INTERRUPT 0
P81/INT1/TI2 ; PORT81/INTERRUPT 1/TIMER 2
OUTPUT
CLK ; CLOCK
P32/SCLK ; PORT32/SERIAL CLOCK
P33/T
X D; PORT33/SERIAL TRANSMIT DATA
P35/
RD
; PORT35/READ STROBE
P36/
WR
; PORT36/WRITE STROBE
P37/
WAIT
/TO1 ; PORT37/WAIT/TIMER 1
X2 ; CRYSTAL OSC 2
TMP90PH02P (TOSHIBA)
INTERRUPT
CONTROLLER
WATCH DOG
TIMER
SERIAL I/O
1CH
RAM
(512 B)
OSC
PORT
0
PROM
(16 KB)
TIMER
8-BIT 2CH
(TIMER 0/1)
TIMER
8-BIT 2CH
(TIMER 2/3)
CPU
AF
BC
DE
HL
A' F'
B' C'
D' E'
H' L'
IX
IY
SP
PC
409
7
1
2
3
8
6
20
21
22
11
10
23
4
5
12 - 19
24 - 31
32 - 39
VCC
X1
X2
CLK
P00 - P07/
D0 - D7
P10 - P17/
A0 - A7
P20 - P27/
A8 - A15
P35/
RD
P36/
WR
VSS (GND)
RESET
EA
P80/INT0
P31/RXD
P32/SCLK
P33/TXD
NMI
P37/
WAIT
/TO1
P81/INT1/TI2
PORT
1
PORT
2
PORT
3

5-1
EA-80
SECTION 5
BLOCK DIAGRAM
1. Communication
In case LLC-8000 sends data “0”
The LLC-8000 turns the voltage at the D.SIG terminal(pin 4 of CN1) on the AU-254 board to 0 V.
It then turns the voltage at the pin 1 of the CPU(IC1) on the SW-952 board to 0.5 V, and the CPU recognizes data as “0”.
In case EA-80 sends data “0”
The EA-80 turns the voltage at the pin 3 of the CPU(IC1) on the SW-952 board to 0 V.
When the voltage at the pin 3 of the CPU is 0 V, the parts, R13, 17 and 18 on the SW-952 board, and also Ra and Rb on the
LLC-8000, turn the voltage at the D.SIG terminal(pin 4 of CN1) on the AU-254 board to 0.5 V. The RxD terminal on the
LLC-8000 recognizes data as “0” because the D.SIG terminal becomes 0.5 V.
2. Audio
The audio input and output levels are shown below. The VOLUME, control knob (RV1) on the SW-952 board adjusts
a sound level from -8 dB to +8 dB. (The RV1 cannot control AUX L IN and AUX R IN signals.)
OUTPUT HS-PHONE(L) HS-PHONE(R) MONI PGM MIC
INPUT (LEVEL)
PGM -10 dB -19 dB -19 dB X-10 dB X
Turning Q1 on makes sound mute.
INCOM -10 dB -19 dB -19 dB X X X
HS-MIC -54 dB -19 dB -19 dB -10 dB X -10 dB
Turning Q2 on makes sound mute.
AUX L -10 dB -19 dB X -16 dB X X
AUX R -10 dB X -19 dB -16 dB X X
Level allowance: ±3 dB
X: No output
Frequency response: 50 through 10 kHz; +3/-10 dB
AUX L IN CN3-1
AUX R IN CN3-2
A.GND
CN1-2
COLD
CN1-6
D.SIG
CN1-4
P.GND
CN1-1
PGM
CN1-3
INCOM
CN1-8
MONI
CN1-5
PGM OUT CN3-4
MIC OUT CN3-5
HS-MIC J1-1
HS-PHONE(L) J2-1
HS-PHONE(R) J2-2
EA-80LLC-8000
[-10dB]
[-10dB]
{-54dB}
{-20dB}
[-20dB] (-19.5dB)
<-18.5dB>
(-36.5dB)
<-35.5dB>
{-37dB}
(-10dB)
{-11dB}
S-MIC SW
PGM-MONI SW
5V
IC1
R18
R13 R173
1RXD
TXD
D1~6 SW1~6
VOLUME
Q1
RV1
Ra
Rb
Q2
MONI
PGM
INCOM
+15V
5V
5V
TXD
RXD
{-10.5dB}
[-17dB]
(-10dB)
<-10dB>
+15V
CN1-7
(-11dB)
<-10dB>
{-11.5dB}
1
2
3
1
2
3
SW-952 BOARD
0dB=0.775Vrms SIGNAL:1KHz VOLUME:CENTER

6-1
EA-80
SW-952
SW-952 -A SIDE-
1-667-870-11,12
SW-952 -B SIDE-
1-667-870-11,12
SECTION 6
BOARD LAYOUTS AND SCHEMATIC DIAGRAM
* : B SIDE
CNI1 B1
D1 A2
D2 A2
D3 B2
D4 C2
D5 C2
D6 A1
*D7 A1
IC1 B1
RV1 C1
SW1 A2
SW2 A2
SW3 B2
SW4 C2
SW5 C2
SW6 A1
X1 A2

6-2 EA-80
AU-254, SW-952
AB C D
2
3
4
5
1
1
2
3
4
5
6
7
8
P20
P21
P22
P23
P24
P25
P10
P11
P12
P13
P14
P15
RxD
TxD
P27
P26
RESET
X2
X1
Vss
Vcc
P32
P35
P36
P37
P80
P81
CLK
P00
P01
P02
P03
P04
P05
P06
P07
P16
P17
MNI
EA
1
2
3
4
5
6
7
8
C1
D1
D2
D3
D4
D5
RV1
C2
R17
R19
R18
X1
R1 R2 R3 R5R6
R12
R7
R8
R9
R10
R11
CN1
R13
R14 R15
R16
R4
D6
D7
IC1
IC3(2/2)
C15
C14
C17
C16
C12
C13 C11
CN2
CL21
CL202 CL201
C29 C30
IC3(1/2)
R19
R20
R22
R25
R24
R26
R27
R23
R21
R36
D1
J2
SW6
SW1
SW2
SW3
SW4
SW5
C3
R100
C108 C109
C104
C105
R35
4.7
25V
20k
0.1
3.9k
27k
150k
9.83MHz
10k 10k 10k 10k10k
1.8k
2.2k
2.2k
2.2k
2.2k
2.2k
470
2.2k 2.2k
1.2k
10k
RB425D-T146
NJM4560M-TE2
47
16V
47
16V
47
16V
33p
33p
0.1 1
NM
NM NM
10
16V 10
16V
NJM4560M-TE2
10k
220k
220k
220k
10k
220k
68
68
100
68
RD5.1ESB
47
16V
1k
470p 470p
470p
470p
270
1/2W
5V
5V
7.5V
7.5V
1
2
3
1
3
2
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37 38
39
40
7
3
2
1
4
8
5
6
+5V
D.SIG
P.GND
A.GND
S-MIC
ATND/CALL
No.1
No.2
No.3
No.4
No.5
ATND/CALL
No.1
No.2
No.3
No.4
No.5
PGM-MONI
+5V
D.SIG
P.GND
A.GND
PGM-MONI
S-MIC
3
3
SW-952 AU-254
TMP90PH-EA80
CPU
VOLUME
RV IN
RV OUT
RV IN
RV OUT
HEAD PHONE
AMP(R)
HEAD PHONE
AMP(L)
**
*
*
*
AU-254 : AUDIO
SW-952 : SWITCH & CPU

6-3
EA-80
AU-254, SW-952
2
3
4
5
ABCD
1
AU-254
SW-952
B-EA80-SERVICE
1
2
3
4
5
6
1
2
3
4
5
6
7
8
9
IC2(1/2)
C9 C8
C10
Q2
Q1
IC1(1/2)
C6
C7
C20
C19
C18
CN3
C5
C3
C4
C2
C1
C21
C24 C23
C22
R39
R40
R41
C28
D3
D2
CL11 CL12 CL13 CL14 CL15
CL17
CL18
CL101
CL31 CL32 CL34 CL35
R34
R101
R102
R18
R14 R13
R17 R16
R15
R37
R38
R10
R9
R8
R7
R11
R12
R33
R32
R31
R30
CN1
IC1(2/2)
R4
R6
R5
IC2(2/2)
R3 R1
R2
J1
R29
R28
C25
C26
C27
R42
C102
C101
C100
C103
C107 C106
NJM4560M-TE2
33p 1
1
DTC143EKA-T146
DTC143EKA-T146
NJM4560M-TE2
100p
1
1
1
1
47
16V
33p
0.1
10
16V
47
16V
47
16V
47
16V 0.1
0.1
150k
150k
150k
1
RD3.6SB-T1
RD3.6SB-T1
NM NM NM NM NM
NM
NM
NM
NM NM NM NM
150k
1k
1k
220k
22k 220k
22k 220k
220k
150k
10k
68k
150k
150k
68k
150k
68
150k
150k
1k
1k
NJM4560M-TE2
1k
150k
220
NJM4560M-TE2
10k 2.2k
22k
22k
22k
1
100p
1
220
470p
470p
470p
470p
470p 470p
7.5V
7.5V
7.5V
7.5V
7.5V
3
2
15
6
7
3
2
1
4
8
5
6
7
4
8
P.GND
A.GND
PGM
D.SIG
MONI
COLD
+15V
INCOM
FG
AUX L IN
AUX R IN
A.GND
A.GND
2
1
1
2
PGM OUT
MIC OUT
SWITCH
SWITCH
BUFFER AMP MIC AMP
MONITOR AMP
MIX AMP
**
**
**
*
*
* Suffix-11 Suffix-12
C100-109
R101,102
NM
NM
470P
1K
LLC-8000
R35 270 1/2W330 1W

6-4 EA-80
AU-254
EA-80 (SY) : S/N 50001 and higher
AU-254 -A SIDE-
1-667-869-12
AU-254 -B SIDE-
1-667-869-12
* : B SIDE
CN1 A2
CN2 B4
CN3 E2
D1 A4
*D2 B3
*D3 B3
*IC1 B2
*IC2 C4
*IC3 D4
J1 C2
J2 D2
*Q1 B3
*Q2 B3