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CORDLESS TELEPHONE
PUBLISHED IN JAPAN, Nov., 1999
SERVICE MANUAL
FILE NO. 2B0-9909
FD-4809


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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
Liquid Crystal Display (LCD)
REDIAL Button
TALK Button
(TONE) Button
MEM (Memory) Button
PAUSE Button
FUNC (Function) Button
DELETE , CH Button
Charging contact
TONE/PULSE Switch
DC in 9V Jack
LINE Modular Jack
Cradle
Base Antenna
IN USE/CHARGE LED
PAGE Button
Charging Contact
VOL/RING Button
Antenna
SELECT Button
CID (Caller ID) Button
Dialpad
Dot matrix display
Date
Caller ID indication example
Time
Caller's telephone number
Caller's name
Number of calls
Battery compartment
900MHz
CALLER ID
FD-4809
OPERATING CONTROLS
HANDSET CONTROLS AND FUNCTIONS
BASE UNIT CONTROLS AND FUNCTIONS
LCD


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3
ALIGNMENT PROCEDURE
Base Unit
Transmitter Section
Connections
Preset
a) Remove the solder on the pattern (refer to the illust. below).
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/CHARGE LED lighting.
Alignment Procedure
Alignment Point Location on Base Main PCB and Base RF PCB
Power
Meter
RF
Test Point
J3
DC IN
9V Jack
AC 120V
60Hz
BASE Unit
AC
Adapter
step
1
Adjustment
VR202
(TX Power)
Remarks
Connect the Power Meter to the RF test point on the Base MAIN PCB.
Adjust VR202 for a -4.0dBm reading on the Power Meter.
VR202
Base RF PCB
S2
T/P Switch
P
T
RF Test Point
J3
DC IN 9V Jack
J1
TEL LINE Jack
Base Main PCB
Remove solder


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4
Receiver Section
Connections
Alignment Point Location on Base Main PCB and Base RF PCB
Preset
a) Remove the solder on the pattern (refer to the illust. below).
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/CHARGE LED lighting.
Alignment Procedure
step
1
Preset to
SG: 1mV
No modulation
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 903.417756 MHz.
Connect the DC Voltmeter to the Discriminator test point. Adjust L1 to
indicate DC 0.90 V.
Adjustment
L1
(Discriminator
Voltage)
RF
Test Point
AF
Terminal
J3
DC IN
9V Jack
AC 120V
60Hz
BASE Unit
-
+
RF SG
DC Voltmeter
AC
Adapter
L1
S2
T/P Switch
P
T
RF Test Point
J3
DC IN 9V Jack
J1
TEL LINE Jack
Base Main PCB
Remove solder
Discriminator Test Point