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29

(*1) Refer to Troubleshooting by Symptom (Base Unit and Charger Unit) (P.36)

Check Point (Base Unit) (P.36)
Power Supply Circuit (P.9)

Check around Power Supply Circuit.

Adjust VDD1 voltage to 1.8 V. 
Refer to Check Point...(B).

Does Base Unit make link with normal working
Handset? 

Check around X1 and IC801 and adjust clock 
frequency.
Refer to Check Point...(G).

NO

NO

NO (*1)

NO

YES

YES

YES

YES

YES

NO

NO

NO

Replace with a new Circuit Board.

Is the modulation OK? 
Refer to Check Point...(K).

Is the voltage of VDD3 about 3.0 V?
Refer to Check Point...(A).

Is there CMD60 (: DECT Tester)?

Does the RF clock (CLK) oscillate at 10.368 MHz in
Base Unit Test Mode?
Refer to Check Point...(G).

Is the voltage of VDD1 about 1.8 V?

YES

Is the NTP value OK? 
Refer to Check Point...(J).

Does Base Unit make link with CMD60 in Base Unit 
Test Mode?
Refer to Check Point...(J).

NO

YES

Base Unit is OK. Check Handset.

YES

YES

Is the Frequency Offset OK? 
Refer to Check Point...(L).

NO

OK

 

30

*1 How to adjust +3.0V:
Execute the command "VDA"
Refer to Things to Do after Replacing IC or X'tal (P.55) for Handset.
*2 How to adjust the frequency of X1:
To see the frequency, execute the command “SFR”, then check the TP_CKM (IC1-57pin).
To adjust frequency, send command “SFR” until the frequency counter becomes13.824 MHz±55HZ.

YES

NO

NO

NO

NO

Is the Frequency Drift OK?
Refer to Check Point...(L).

YES

Is the Sensitivity Receiver OK?
Refer to Check Point...(M).

YES

Is the Timing OK?
Refer to Check Point...(N).

YES

Is the Power RAMP OK?
Refer to Check Point...(O).

Replace with a new Circuit Board.

Check around Power Supply Circuit/Reset Circuit.

Adjust +3.0V Vottage  to 3.0V

Does Handset make link with Base Unit?
(Correct working unit)

Check around X1 and RF module and adjust
clock frequency. 

NO

NO

NO

NO

Is the voltage of TP VBAT about 2.2~2.8 V?

Is the voltage of TP VDDC about 1.2 V?

YES

YES

YES

YES

Is the voltage of TP 3.0 V about 3.0 V?

Does the RF clock (CLK) oscillate: 13.824 MHz
in Handset Test Mode?

Handset is OK. Check Base Unit.

YES

OR

Check the batteries.

*1

*2

31

1. Re-register the checked Handset to the checked Base Unit, and Regular HS to Regular BU.

If you need to register a handset, refer to Registering a Handset to a Base Unit in the Operating Instructions.

1. Prepare Regular HS (Handset) and Regular BU (Base unit).
2. a. Re-register regular HS (Normal mode) to Base Unit (to be checked).
        If this operation fails in some ways, the Base Unit is defective.
    b. Re-register Handset (to be checked) to regular BU (Normal mode). 
        If this operation fails in some ways, the Handset is defective.

Base Unit is defective

Handset is defective

START

Registration of 

Regular HS to

Base Unit

Registration of 

Handset to

Regular BU

(other checkings)

Registration of Handset to Base Unit 

(checked ones)

Registration of Regular HS to Regular BU

Yes

No

No

Yes

32

Each item (1 ~ 3) of RF Check Flowchart corresponds to Check Table for RF part (P.33).
Please refer to the each item.

(*1) Base unit - refer to (G) of Check Point (Base Unit) (P.36)
      Handset - refer to (H) of Check Point (Handset) (P.40)

Start

Link

confirmation

Normal

1

Control

signal

confirmation

X'tal

Frequency

confirmation

 Range

confirmation

Normal

Check Range: Compare with a regular unit.

Check DSP interface parts.
(RF Block <->DSP on BU/HS P.C.B)

Adjust X'tal Frequency. (*1)

GOOD

4

2

3

OK

OK

NG

NG

NG

NG

OK

OK