Panasonic KX-FC255CX-S, Service Manual, Page: 138 / 256

138
KX-FC255CX-S
( G )* Charge Detection (OFF)
Check
- 1. Stop supplying 3.5V to TP20(+) and TP21(-).
2. Execute the command “Backloff” then “charge”.
3. Confirm that the returned value is 00 (hex). IC1, Q4, Q5,
Q9, D6, L4, L5,
R5, R6, F1,
R8, D7, D8, R7
( H )* Battery Monitor Check - 1. Apply 2.25V between BATT and GND.
2. Execute the command “readbatt”.
It assumes that the return value is XX.
a) 1E XX 2C: No need to adjust
b) XX: 18 ~ 1D: Need to adjust
XX: 2D ~ 32: Need to adjust
Write AD value of 2.25V to FLASH.
ex) read data: XX = 1C, write data: YY = 1C
read data: XX = 2D, write data: YY = 2D
FLASH = 0004(Low Voltage) write “YY”
Execute the command “wreeprom 00 04 01 YY”.
FLASH = 0005(No Voltage) write “YY - 1D”
Execute the command “wreeprom 00 05 01 ZZ”.
FLASH = 000A(Low Voltage BL) write “YY - 06”
Execute the command “wreeprom 00 0A 01 WW”.
Note:
ZZ = YY - 1D, WW = YY - 06
No Voltage writing data limit is ‘00’.
c) XX: 00 ~ 17: Reject
XX: 33 ~ FF: Reject
IC1, F1, C1,
C3, R12
( I ) Battery Low Confirma-
tion
- 1. Apply 2.40V between J1 (BATT+) and J2 (BATT-).
2. Confirm that there is no flashing of Battery Icon.
3. Apply 2.25V ± 0.08V between J1 (BATT+) and J2 (BATT-).
4. Confirm that there is flashing of Battery Icon. IC1, F1, C1,
C3, R12
( J )* BBIC Clock Adjustment CLK 1. Apply 2.5V between B) and BATTERY(-) with DC power.
2. Execute the command “conttx”.
3. Input Command “rdeeprom 00 01 01”, then you can confirm the current value.
4. Adjust the frequency of CLK executing the command “setfreq 00 xx (where xx
is the value)” so that the reading of the frequency counter is 10.368000MHz ±
10Hz.
Note:
CLK is displayed only for a few seconds when executing the command “conttx”
after battery is inserted.
IC1, X1, C6,
C7, R19, IC4,
C57
( K )* Transmitted Power Con-
firmation
- Remove the Antenna before starting step from 1 to 4.
1. Configure the DECT tester (CMD60) as follows;
<Setting>
• Test mode: PP
• RFPI: 0102030405
• Traffic Carrier: 5
• Traffic Slot: 4
• Mode: Loopback
• RF LEVEL = -70dBm
2. Execute the command “regcmd60 01 02 03 04 05”.
3. Initiate connection from DECT tester.
4. Confirm that the NTP value at ANT is 20dBm ~ 25dBm.
IC1, IC4, C66,
C58, C57,
C50, C53,
C52, R52,
C60, C61
( L )* Modulation Check and
Adjustment
- Follow steps 1 to 3 of (K) .
4.Confirm that the B-Field Modulation is -350 ~ -400/+320 ~ +370kHz/div using
data type Fig 31.
5.Adjust the B-Field Modulation if required. (Execute the command “Readmod”
and “wrtmod xx”, where xx is the value.)
IC1, IC4, C66,
C58, C57,
C50, C53,
C52, R52,
C60, C61
( M ) Frequency Offset Confir-
mation
- Follow steps 1 to 3 of (K) .
4.Confirm that the frequency Offset is < ± 45kHz.
IC1, IC4, C66,
C58, C57,
C50, C53,
C52, R52,
C60, C61
( N ) Frequency Drift Confir-
mation
- Follow steps 1 to 3 of (K) .
4.Confirm that the frequency Drift is < ± 30kHz/ms.
IC1, IC4, C66,
C58, C57,
C50, C53,
C52, R52,
C60, C61
( O ) Sensitivity Receiver
Confirmation
- Follow steps 1 to 3 of (K) .
4.Set DECT tester power to -90dBm.
5.Confirm that the BER is < 1000ppm.
IC1, IC4, C66,
C58, C57,
C50, C53,
C52, R52,
C60, C61
Items Check
Point
Procedure Check or
Replace Parts