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KX-TG3721BX/KX-TG3722BX/KX-TGA371BX
TABLE OF CONTENTS
PAGE
PAGE
1 Safety Precautions
-----------------------------------------------
4
1.1. For Service Technicians --------------------------------- 4
2 Warning
--------------------------------------------------------------
4
2.1. Battery Caution--------------------------------------------- 4
2.2. About Lead Free Solder (PbF: Pb free)-------------- 4
2.3. Discarding of P. C. Board-------------------------------- 5
3 Specifications
-----------------------------------------------------
6
4 Technical Descriptions
-----------------------------------------
7
4.1. FHSS Description ----------------------------------------- 7
4.2. Block Diagram (Base Unit_Main)---------------------- 9
4.3. Tel Interface Circuit---------------------------------------10
4.4. Block Diagram (Base Unit_RF Part) -----------------11
4.5. Circuit Operation (Base Unit)--------------------------12
4.6. Block Diagram (Handset)-------------------------------18
4.7. Block Diagram (Handset_RF Part)-------------------19
4.8. Circuit Operation (Handset)----------------------------20
4.9. Behavior of Electric Power Failure -------------------22
4.10. Circuit Operation (Charger Unit) ----------------------22
4.11. Signal Route -----------------------------------------------23
5 Location of Controls and Components
------------------
25
6 Installation Instructions
---------------------------------------
25
7 Operating Instructions
-----------------------------------------
25
8 Test Mode
----------------------------------------------------------
26
8.1. Engineering Mode ----------------------------------------26
8.2. Copying Phonebook Items when Repairing -------30
9 Service Mode
-----------------------------------------------------
32
9.1. How to Clear User Setting------------------------------32
10 Troubleshooting Guide
----------------------------------------
33
10.1. Troubleshooting Flowchart -----------------------------33
11 Disassembly and Assembly Instructions
---------------
44
11.1. Disassembly Instructions -------------------------------44
11.2. How to Replace the Base unit LCD ------------------48
11.3. How to Replace the Handset LCD -------------------50
12 Measurements and Adjustments
---------------------------
51
12.1. Equipment Required -------------------------------------51
12.2. The Setting Method of JIG -----------------------------51
12.3. Adjustment of Base Unit --------------------------------55
12.4. Adjustment of Handset ----------------------------------56
12.5. Adjustment Standard (Base Unit)---------------------59
12.6. Adjustment Standard (Charger Unit)-----------------60
12.7. Adjustment Standard (Handset) ----------------------61
12.8. Things to Do after Replacing IC or X'tal ------------62
12.9. How to Check the Handset Receiver----------------64
12.10. Frequency Table (MHz) ---------------------------------65
13 Miscellaneous
----------------------------------------------------
66
13.1. How to Replace the LLP (Leadless Leadframe
Package) IC------------------------------------------------66
13.2. How to Replace the Flat Package IC ----------------68
13.3. How to Replace the Shield Case ---------------------70
13.4. Terminal Guide of the ICs, Transistors and
Diodes -------------------------------------------------------72
14 Schematic Diagram
---------------------------------------------
73
14.1. For Schematic Diagram---------------------------------73
14.2. Schematic Diagram (Base Unit_Main) --------------74
14.3. Schematic Diagram (Base Unit_RF)-----------------76
14.4. Schematic Diagram (Base Unit_Operation) -------77
14.5. Schematic Diagram (Handset_Main) ----------------78
14.6. Schematic Diagram (Charger Unit) -----------------80
15 Printed Circuit Board
------------------------------------------
81
15.1. Circuit Board (Base Unit_Main) ---------------------- 81
15.2. Circuit Board (Base Unit_Operation)---------------- 83
15.3. Circuit Board (Handset_Main) ------------------------ 85
15.4. Circuit Board (Charger Unit)--------------------------- 87
16 Exploded View and Replacement Parts List
-----------
88
16.1. Cabinet and Electrical Parts (Base Unit) ----------- 88
16.2. Cabinet and Electrical Parts (Handset)------------- 89
16.3. Cabinet and Electrical Parts (Charger Unit) ------- 90
16.4. Accessories------------------------------------------------ 91
16.5. Replacement Parts List--------------------------------- 92