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49

Telephone Line Interface (P.10)
Check Link (P.41)
How to Check the Handset Speaker or Receiver (P.77)

Power Supply Circuit (P.9)

(*1) When replacing FLASH MEMORY 1 (IC602), TAM data needs to be written to it. Refer to Base Unit (P.74) of Things to Do
after Replacing IC.

50

Signal Route (P.14)

Signal Route (P.14)

51

If your unit has below symptoms, follow the instructions in remedy column. Remedies depend on whether you have DECT tester
(*1) or not. 

(*1) A general repair is possible even if you don’t have the DECT tester because it is for confirming the levels, such as Acoustic
level in detail.
(*2) Refer to Check Point (Base Unit) (P.51)

Please follow the items below when BBIC, EEPROM or FLASH is replaced.

After the measuring, suck up the solder of TP.
*: PC Setting (P.67) is required beforehand.
The connections of simulator equipments are as shown in Adjustment Standard (Base Unit) (P.69).

Items

Check 

Point

Procedure

Check or 

Replace Parts

(A)

4.0V Supply Confirma-

tion

TP302

1. Confirm that the voltage between test point TP302 and GND is 4.0V ± 0.2V.

C301, C336, 

IC303, Q305, 

L303, D305, 

R331, R332, 

R333, C334

(B)

3.3V Supply Confirma-

tion

TP3.3V

1. Confirm that the voltage between test point TP3.3V and GND is 3.3V ± 0.2V.

IC301, C302, 

C837

(C)

2.5V Supply Confirma-

tion

TP2.5V

1. Confirm that the voltage between test point TP2.5V and GND is 2.5V ± 0.2V.

IC302, R223, 

R224, C332

(D)

3.0V Supply Confirma-

tion

TP3.0V

1. Confirm that the voltage between test point TP3.0V and GND is 3V ± 0.2V.

Q302, R341, 
R343, R344, 

C304

(E)

1.8V Supply Confirma-

tion

TP1.8V

1. Confirm that the voltage between test point TP1.8V and GND is 1.8V ± 0.1V. 

Q301, R342, 

C303

(F)*

BBIC Confirmation

-

1. BBIC Confirmation (Execute the command “getchk”).
2. Confirm the returned checksum value.

Connection of checksum value and program number is shown below.

IC501, X501, 

R503, C510, 
C511, C504, 

R502, 

R510~R515, 

IC603

(G)* EEPROM Confirmation

-

1. EEPROM Confirmation (Execute the command “ChkTG8280XXrevYY.bat”).

XX: country code YY: revision number

2. Confirm the returned checksum value.
3. The checksum is displayed in the last output line.

“YY” and “checksum” vary depending on the country version. You can find them
in the batch file, PQZZ- mentioned in JIG and PC (P.67).

IC502, R504, 

R505, R506, 

C515

52

(H)* BBIC Clock Adjustment

CLK

1. Check X’tal Frequency. (10.368 MHz ± 100 Hz).

Input Command “rdeeprom 00 01 01”, then you can confirm the current value.

2. If the frequency is not 10.368 MHz ± 100Hz, Adjust the frequency of CLK exe-

cuting the command “setfreq xx (where xx is the value)” so that the reading of
the frequency counter is 10.368000 MHz ± 20 Hz.

IC801, R803, 

R804, R813, 
C808, C813, 
X501, R503, 

C510, C511

(I)* Hookswitch Check with 

DC Characteristics

-

1. Connect CN101 (Line 1)/CN201 (Line 2) (Telephone Socket) to Tel-simulator

which is connected with 600 

Ω.

2. Set line voltage to 48V and line current to 40mA at off-hook condition of nor-

mal telephone.

3. Execute the command “hookoff”
4. Confirm that the line current is 40mA ± 5mA.
5. Execute the command “hookon”.
6. Confirm that the line current is less than + 0.8mA.

<Line 1>

L101, L102, 

SA101, D101, 

C102, C103, 

Q101, PC102, 

Q103, R105, 
R106, R107, 

Q103, R108

<Line 2>

L201, L202, 

SA201, D201, 

C202, C203, 

Q201, PC202, 

R205, R206, 

Q203, R208

(J) DTMF Generator Check

-

1. Connect CN101 (Line 1)/CN201 (Line 2) (Telephone Socket) to DTMF tester.

(Road=600 

Ω)

2. Link Handset and push dial key.
3. Confirm DTMF character.
4. Confirm that the high Group is -3 ± 2 dBm.
5. Confirm that the low Group is -6 ± 2 dBm.

<Line 1>

IC501, R152, 

R151, C128, 
Q105, R128, 

R124, R125

<Line 2>

IC501, C264, 

T202, R225, 

C228, Q205, 
R218, R224, 

R225

(K)* Transmitted Power Con-

firmation

-

Remove the Antenna before starting step from 1 to 7.

1. Configure the DECT tester (CMD60) as follows;

<Setting>

• Short A_1 and GND.
• Test mode: FP
• Traffic Carrier: 5
• Traffic  Slot:  4
• Mode: Loopback
• PMID: 00000
• RF LEVEL = -70dBm.

2. Execute the command “testmode”.
3. Execute the command “sendchar dmv 2 2”.
4. Check that “Signalling Status” has been set to “Locked”, then press “ACCEPT

RFPI”.

5. Initiate connection from Dect tester (“set up connect”)
6. Execute the command “ANT1”.
7. Confirm that the NTP value at ANT is 20dBm ~ 25dBm.

IC501, IC801, 

C817, C825, 

D801, L804, 

R805, R808, 
R803, R804, 
R816, R817, 
R810, R819, 

R820

(L)* Modulation Check and 

Adjustment

-

Follow steps 1 to 6 of (K).

7.Confirm that the B-Field Modulation is -350 ~ -400/+320 ~ +370kHz/div using
data type Fig31.
8.Adjust the B-Field Modulation if required. (Execute the command “readmod”
and “wrtmod xx”, where xx is the value.)

IC501, IC801, 

C817, C825, 

D801, L804, 

R805, R808, 
R803, R804, 
R816, R817, 
R810, R819, 

R820

(M)* Frequency Offset Check

-

Follow steps 1 to 6 of (K).

7.Confirm that the frequency offset is < ± 45kHz.

IC501, IC801, 

C817, C825, 

D801, L804, 

R805, R808, 
R803, R804, 
R816, R817, 
R810, R819, 

R820

Items

Check 

Point

Procedure

Check or 

Replace Parts