KX-TG7321RUC, KX-TG7321RUS, KX-TGA731RUC, KX-TGA731RUS (serv.man2) - Panasonic Telephone Service Manual (repair manual). Page 3

3

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. Block Diagram (Base Unit) ------------------------------ 7
4.2. Circuit Operation (Base Unit) --------------------------- 8
4.3. Block Diagram (Handset)-------------------------------11
4.4. Circuit Operation (Handset)----------------------------12
4.5. Circuit Operation (Charger Unit) ----------------------13
4.6. Signal Route -----------------------------------------------14

5 Location of Controls and Components ------------------16

5.1. Controls -----------------------------------------------------16

6 Installation Instructions ---------------------------------------17

6.1. Connections------------------------------------------------17
6.2. Battery-------------------------------------------------------18

7 Operating Instructions-----------------------------------------19

7.1. Programmable Settings ---------------------------------19
7.2. Registering a Handset to the Base Unit ------------21
7.3. Copying Phoneboo Entries-----------------------------21
7.4. Dialling Mode (Tone/Pulse) ----------------------------22
7.5. Error Messages -------------------------------------------22
7.6. Troubleshooting-------------------------------------------23
7.7. For Service Hint-------------------------------------------26

8 Service Mode -----------------------------------------------------27

8.1. Engineering Mode ----------------------------------------27
8.2. Copying Phonebook Items when Repairing -------31
8.3. How to Clear User Setting------------------------------33

9 Troubleshooting Guide ----------------------------------------34

9.1. Troubleshooting Flowchart -----------------------------34
9.2. Troubleshooting by Symptom (Base Unit and

Charger Unit) ----------------------------------------------46

9.3. Troubleshooting by Symptom (Handset) -----------50
9.4. How to Replace the Flat Package IC----------------54
9.5. How to Replace the LLP (Leadless Leadframe

Package) IC------------------------------------------------56

10 Disassembly and Assembly Instructions ---------------58

10.1. Disassembly Instructions -------------------------------58
10.2. How to Replace the Handset LCD -------------------62

11 Measurements and Adjustments---------------------------63

11.1. The Setting Method of JIG (Base Unit) -------------63
11.2. Adjustment Standard (Base Unit)---------------------65
11.3. Adjustment Standard (Charger Unit)-----------------66
11.4. The Setting Method of JIG (Handset) ---------------67
11.5. Adjustment Standard (Handset) ----------------------69
11.6. Things to Do after Replacing IC or X'tal ------------70
11.7. RF Specification-------------------------------------------72
11.8. How to Check the Handset Speaker or

Receiver ----------------------------------------------------73

11.9. Frequency Table (MHz) ---------------------------------73

12 Schematic Diagram ---------------------------------------------74

12.1. For Schematic Diagram---------------------------------74
12.2. Schematic Diagram (Base Unit) ----------------------76
12.3. Schematic Diagram (Base Unit_Operation) -------78
12.4. Schematic Diagram (Handset) ------------------------80

12.5. Schematic Diagram (Charger Unit)------------------ 82

13 Printed Circuit Board ------------------------------------------ 83

13.1. Circuit Board (Base Unit_MAIN) --------------------- 83
13.2. Circuit Board (Base Unit_Operation)---------------- 85
13.3. Circuit Board (Handset) -------------------------------- 87
13.4. Circuit Board (Charger Unit)--------------------------- 89

14 Appendix Information of Schematic Diagram --------- 90

14.1. CPU Data (Base Unit) ---------------------------------- 90
14.2. CPU Data (Handset) ------------------------------------ 92
14.3. Terminal Guide of the ICs, Transistors and

Diodes ------------------------------------------------------ 94

15 Exploded View and Replacement Parts List ----------- 95

15.1. Cabinet and Electric Parts (Base Unit) ------------- 95
15.2. Cabinet and Electric Parts (Handset) --------------- 96
15.3. Cabinet and Electric Parts (Charger Unit) --------- 97
15.4. Accessories and Packing Materials ----------------- 98
15.5. Replacement Part List -------------------------------- 100