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SERVICE MANUAL
PUBLISHED IN JAPAN, May, 2001
FILE NO. 2B0-200104
FT-8981
CORDLESS TELEPHONE


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-- 1 --
CONTENTS
SAFETY PRECAUTIONS ...................................................................................................................... 1
OPERATING CONTROLS ..................................................................................................................... 2
ANSWERING MACHINE ....................................................................................................................... 3
ALIGNMENT PROCEDURE .................................................................................................................. 4
BLOCK DIAGRAMS ............................................................................................................................... 8
SCHEMATIC DIAGRAMS .................................................................................................................... 10
TROUBLESHOOTING HINTS ............................................................................................................. 14
IC AND TRANSISTOR VOLTAGE CHART ......................................................................................... 21
SEMICONDUCTOR LEAD IDENTIFICATION ..................................................................................... 26
ELECTRICAL PARTS LOCATION ...................................................................................................... 28
WIRING DIAGRAMS ............................................................................................................................ 30
EXPLODED VIEW AND MECHANICAL PARTS LIST ........................................................................ 32
PARTS LIST ......................................................................................................................................... 34
ASSEMBLY PARTS LIST .................................................................................................................... 48
SPECIFICATIONS ............................................................................................................................... 49
SAFETY PRECAUTIONS
Before returning any models to the customer, a safety check of the entire instrument should be made.
The service technician must be sure that no protective device built into the instrument by the manufacturer
has become defective or inadvertently degraded during servicing.
1. WARNING:
Alterations of the design or circuitry of these models should not be made.
Any design changes or additions such as, but not limited to, circuit modifications, auxiliary speaker
jacks, switches, grounding, active or passive circuitry, etc. may alter the safety characteristics of these
models and potentially create a hazardous situation for the user.
Any design alterations or additions will void the manufacturer's warranty and will further relieve the
manufacturer of responsibility for personal injury or property damage resulting therefrom.
2. PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special characteristics. These characteristics
often pass unnoticed and the protection afforded by them cannot necessarily be obtained by using
replacement components rated for higher voltage, 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 a
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.


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-- 2 --
DC IN 9V Jack
TEL LINE MODULAR Jack
Antenna
POWER
PAGE
IN USE
CHARGE
MENU
SET
MIC
TIME
VOLUME
CHARGE LED
IN USE LED
POWER LED
PAGE Button
REC MEMO/2WAY Button
ANSWER Button
SKIP FF/SELECT
Button
PLAY/STOP Button
TIME Button
DELETE Button
VOLUME
Button
VOLUME
Button
Charging Contact
GREETING Button
ANSWER
S
K
IP
PLA
Y/
S
T
O
P
D
E
LE
TE
DIGITAL CALLER ID / ANSWERING SYSTEM
CORDLESS TELEPHONE
MENU Button
SET Button
REC
MEMO/2WAY
SELECT
SELECT
REW REPEAT/SELECT
Button
COMPANDOR NOISE REDUCTION
GREETING
OPERATING CONTROLS
BASE UNIT CONTROLS AND FUNCTIONS
TALK Button
(TONE) Button
MEM (Memory) Button
PAUSE Button
Charging contact
DELETE
CH Button
FUNC Button
Antenna
CID Button
SELECT Button
Dialpad
Rechargeable
Battery Pack (back)
LCD Display
VOL/RING Button
L.D. Button
(PULSE) Button
FLASH Button
LOCAL Button
TALK
ABC
2
JKL
5
TUV
8
OPER
TONE
MEM
PAUSE
FUNC
CH
DELETE
LOCAL
L.D.
SELECT
REDIAL
FLASH
VOL/
RING
CID
0
DEF
3
MNO
6
WX
YZ
PQ
RS
9
#
#
GHI
4
7
1
COMPANDOR NOISE REDUCTION
REDIAL Button
LCD
Number of calls
Dot matrix display
Date
Time
Caller's telephone number
Caller's name
HANDSET CONTROLS AND FUNCTIONS
SETTING THE DIAL MODE
1 Press and hold FLASH until you
hear a confirmation tone.
2 To set the dial mode for pulse
dialing, press # . Or to set the dial
mode for tone dialing press
. A
confirmation tone sounds to
indicate the setting is complete.


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ANSWERING MACHINE
SETTING THE CLOCK
1. Press MENU twice, then press SET .
2. Select the day of the week by pressing SELECT
or SELECT
. When the correct day is announced,
press SET .
3. Select the hour by pressing
SELECT
or SELECT
. When the correct hour is announced, press
SET
.
4. Select the minute by pressing
SELECT
or
SELECT
. When the correct minute is announced,
press SET .
5. Select AM/PM by pressing
SELECT
or SELECT
. When AM or PM is announced, press SET .
RECORDING AND SETTING THE GREETING MESSAGE
To record the greeting message:
1. Press MENU once, then press REC MEMO/2WAY
.
2. Start to record your message after the guidance.
3. Press REC MEMO/2WAY
or PLAY/STOP to finish recording.
To change the greeting message:
1. Press GREETING .
2. Press
SELECT
or SELECT
to change to other.
3. Press PLAY/STOP to exit the system.
SETTING THE SECURITY CODE (PIN):
1. Press MENU three times.
2. Press SET to change the security code (PIN).
3. Press
SELECT
or SELECT
until the desired number appears.
4. Press SET to set the security code (PIN).


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Base Main PCB
RT301
RT3
CT1
J1
TEL LINE Jack
J2
DC IN 9V Jack
RF Test Point
Base RF PCB
Alignment Point Location on Base Main PCB and Base RF PCB
ALIGNMENT PROCEDURE
Base Unit
Transmitter Section
Connections
Preset
Press and hold the "ANSWER" key about 5.0 seconds while turning the 7. SEG LED shows "8" .
Power
Meter
RF
Test Point
BASE Unit
J2
DC IN
9V Jack
1kHz -15dBm
AF GEN.
AC 120V
60Hz
Frequency
Counter
Deviation
Meter
RF
Test Point
J1
TEL Line
Jack
AC
Adapter
Alignment Procedure
step
1
2
3
Adjustment
RT301
(TX Power)
CT1
(TX Frequency)
RT3
(TX Modulation)
Remarks
Connect the Power Meter to the RF test point on the Base MAIN PCB.
Adjust RT301 for a -6.0dBm reading on the Power Meter.
Connect the Frequency Counter to the RF test point on the Base MAIN
PCB. Adjust CT1 to make sure that the frequency is 926.897468 MHz.
Press the "SKIP / FF" key to enter the TEST MODE "9". Connect the AF
Generator to the TEL Line Jack on the Base Main PCB. Make sure that
the output is 1 kHz -15dBm from the AF Generator.
Connect the Deviation Meter to the RF test point on the Base MAIN PCB.
Adjust RT3 to indicate ±8 kHz Dev.