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CORDLESS TELEPHONE
PUBLISHED IN JAPAN, Aug., 2000
SERVICE MANUAL
FILE NO. 2B0-200006
FT-8000


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1
CONTENTS
SAFETY PRECAUTIONS ............................................................................................................ 1
OPERATING CONTROLS ........................................................................................................... 2
ALIGNMENT PROCEDURE ........................................................................................................ 3
BLOCK DIAGRAMS ..................................................................................................................... 7
SCHEMATIC DIAGRAMS ............................................................................................................ 9
TROUBLESHOOTING HINTS ................................................................................................... 13
IC AND TRANSISTOR VOLTAGE CHART ............................................................................... 20
SEMICONDUCTOR LEAD IDENTIFICATION ........................................................................... 24
ELECTRICAL PARTS LOCATION ............................................................................................. 26
WIRING DIAGRAMS .................................................................................................................28
EXPLODED VIEW AND MECHANICAL PARTS LIST ............................................................... 30
PARTS LIST ............................................................................................................................... 34
ASSEMBLY PARTS LIST .......................................................................................................... 44
SPECIFICATIONS ..................................................................................................................... 45
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 manufacture
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 indentified 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
OPERATING CONTROLS
HANDSET CONTROLS AND FUNCTIONS
BASE UNIT CONTROLS AND FUNCTIONS
TALK Button
(TONE) Button
MEM (Memory) Button
MUTE Button
Charging contact
PULSE/TONE Switch
DC IN 9V Jack
TEL LINE Jack
Antenna
IN USE/CHARGE LED
PAGE Button
Charging Contact
VOL/RING Button
CH (channel)Button
Antenna
FLASH Button
RDL/P (Redial/Pause)Button
Dialpad
Rechargeable
Battery Pack(back)
TALK/BATT LOW LED
Hook
TALK
TALK
ABC
IN USE
PAGE
CHARGE
2
JKL
5
TUV
8
OPER
TONE
MEM
MUTE
CH
VOL/RING
RLD/P
FLASH
0
DEF
3
MNO
6
WX
YZ
PQ
RS
9
#
GHI
4
7
1
BATT LOW
CORDLESS
TELEPHONE
COMPANDOR NOISE REDUCTION
900MHz
FT-8000
COMPANDOR NOISE REDUCTION
900MHz


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3
ALIGNMENT PROCEDURE
Base Unit
Transmitter Section
Connections
Preset
a) Connect the base RF unit to the base main unit.
b) Set the "TONE / PULSE" switch to PULSE.
c) Connect the AC adapter to the base unit while pressing the "PAGE" key, and keep pressing it continuously for
approximate 2 sectonds.
d) Release the "PAGE" key when entering TEST mode 1 with IN USE LED lighting.
Alignment Procedure
Alignment Point Location on Base Main PCB and Base RF PCB
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 -6.5dBm 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 "PAGE" key to enter the TEST Mode 2. Connect the AF Generator
to the TEL Line Jack on the Base Main PCB. Make sure that the output is 1
kHz 138 mV 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.
Power
Meter
RF
Test Point
BASE Unit
J2
DC IN
9V Jack
1kHz 138mV
AF GEN.
AC 120V
60Hz
Frequency
Counter
Deviation
Mater
RF
Test Point
J1
TEL Line
Jack
AC
Adapter
S2
T/P Switch
P
T
RF Test Point
J2
DC IN 9V Jack
J1
TEL LINE Jack
Base Main PCB
RT3
RT301
CT1
Base RF PCB


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4
Receiver Section
Connections
Alignment Point Location on Base Main PCB and Base RF PCB
Preset
a) Connect the base RF unit to the base main unit.
b) Set the "TONE/PULSE" switch to PULSE.
c) Connect the AC adapter to the base unit while pressing the "PAGE" key, and keep pressing it continuously for
approximate 2 seconds.
d) Release the "PAGE" key when entering TEST mode 1 with IN USE LED lighting.
Alignment Procedure
step
1
2
3
Preset to
SG: 1mV
No modulation
SG: 1mV
1 kHz ±8kHz
deviation
SG: -6.0 dB
µµµµµV
1kHz ±8kHz
Deviation
Remarks
Press the "PAGE" key for 3 times to enter the TEST Mode 4. Connect the
RF Signal Generator to the RF test point on the Base MAIN PCB. Make
sure that the frequency is 902.952467 MHz.
Connect the DC Voltmeter to the AF Terminal of RT1. Adjust L3 to indicate
DC 1.00 V.
Connect the AC Voltmeter across a 600-ohm dummy to the Telephone Line
Jack. Adjust RT2 for a 195 mV reading on the AC voltmeter.
Press the "PAGE" key to enter the TEST Mode 5. Make sure that the
frequency of RF SG output is 902.952467 MHz. Adjust RT1 to turn to the
point where the CHG LED just turns on.
Adjustment
L3
(Discriminator
Voltage)
RT2
(RX AF
Voltage)
RT1
(SQ Point)
AC Voltmeter
BASE Unit
AF
Terminal
Dummy Load
(600-ohm)
RF SG
AC 120V
60Hz
J2
DC IN 9V Jack
+
RF
Test Point
J1
TEL Line
Jack
AC
Adapter
DC Voltmeter
-
+
-
Base Main PCB
S2
T/P Switch
RT2
P
T
RT1
J2
DC IN 9V Jack
J1
TEL LINE Jack
L3
AF Terminal
RF Test Point