KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 1 Safety Precautions 1.1. For Service Technicians • Repair service shall be provided in accordance with repair technology information such as service manual so as to pre- vent fires, injury or electric shock, which can be caused by improper repair work.
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 2.2.1. Suggested PbF Solder There are several types of PbF solder available commercially. While this product is manufactured using Tin, Silver, and Copper (Sn+Ag+Cu), you can also use Tin and Copper (Sn+Cu) or Tin, Zinc, and Bismuth (Sn+Zn+Bi). Please check the manufacturer’s specific instructions for the melting points of their products and any precautions for using their product with other materials.
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 3 Specifications Note: • Design and specifications are subject to change without notice. Note for Service: • Operation range: Up to 300 m outdoors, Up to 50 m indoors, depending on the condition. • Analog telephone connection: Telephone Line...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 4.2. Circuit Operation (Base Unit) 4.2.1. Outline Base Unit consists of the following ICs as shown in Block Diagram (Base Unit) (P.7). • DECT BBIC (Base Band IC): IC7 - Handling all the audio, signal and data processing needed in a DECT base unit...
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 4.2.2. Power Supply Circuit The power is supplied to the DECT BBIC, RF Module, EEPROM and Charge Contact from AC Adaptor (+6.5 V) as shown in Fig.101. The power supply is as follows; • DECT BBIC (IC7): DC Jack (+6.5 V) → IC1 → Q9 → IC7 DC Jack (+6.5 V) →...
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 4.2.3. Telephone Line Interface <Function> • Bell signal detection • Clip signal detection • ON/OFF hook circuit Bell & Clip (: Calling Line Identification Presentation: Caller ID) signal detection: In the standby mode, Q3 is open to cut the DC loop current and decrease the ring load.
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 4.4. Circuit Operation (Handset) 4.4.1. Outline Handset consists of the following ICs as shown in Block Diagram (Handset) (P.11). • DECT BBIC (Base Band IC): IC1 - All data signals (forming/analyzing ACK or CMD signal) - All interfaces (ex: Key, Detector Circuit, Charge, DC/DC Converter, EEPROM, LCD, RF Power Amp.)
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 6 Installation Instructions 6.2. Battery 6.2.1. Battery Installation and Replace- 6.1. Connections ment See For Service Hint (P.25)
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In that case, by recharging the battery as mentioned above, you will get a correct indication of the battery strength. 6.2.3. Battery Level 6.2.4. Panasonic Ni-MH Battery Performance (supplied batteries)
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT *1 The item will not be reset when pressing key of the handset. Refer to How to Clear User Setting (P.32). *2 The item will not be reset when pressing keys. Refer to How to Clear User Setting (P.32).
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 7.2.1. Deregistering a Handset 7.3. Copying Phonebook Entries You can copy phonebook entries to the phonebook of another compatible Panasonic handset. Note: Category settings for phonebook entries are not copied. 7.3.1. Copying All Entries 7.4. Dialling Mode...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 8 Service Mode 8.1. Engineering Mode 8.1.1. Base Unit...
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Frequently Used Items (Base Unit) ex.) Items Address Default Data New Data Remarks C-ID (FSK) sensitivity 04 D6 01 (6 dB up) 02 (12 dB up) When hex changes from “00” to “01” or “02”, gain increases by 6 dB or 12 dB.
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Frequently Used Items (Handset) ex.) Items Address Default Data New Data Possible Adjusted Possible Adjusted Remarks Value MAX (hex) Value MIN (hex) Sending level 00 06 Adjusted value Given value (*2) Receiving level 00 07 Adjust value Given value...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 8.2. Copying Phonebook Items when Repairing You can copy the handset phonebook to another (compatible Panasonic) handset. This will help to save the original phonebook data which the customer has registered. Available models: KX-TG8011/8012/8021 Refer to the following procedures.
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Note: • BS=Base Unit , HS=Handset • If the max number of handsets are already registered to the base unit, a new handset cannot be registered. • To register the handset, refer to Registering a Handset to a Base Unit (P.20) •...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 8.3. How to Clear User Setting Units are reset to the Factory settings by this operation (Erase recorded Voice messages*, stored Phone numbers, Caller list and etc.) Note: • Some menus are not reset. Refer to Operating Instructions (P.19).
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9 Troubleshooting Guide 9.1. Troubleshooting Flowchart Flow Chart Cross Reference: Check Power (P.34) Bell Reception (P.44) Check Battery Charge (P.35) Check Link (P.36) Check the RF part (P.40) Check Handset Transmission (P.43) Check Handset Reception (P.43) Signal Route (P.14) Check Caller ID (P.43)
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.1.1. Check Power 9.1.1.1. Base Unit Is the AC Adaptor inserted into AC outlet? (*1) Cross Reference: Note: Power Supply Circuit (P.9) (*1) Refer to Specifications (P.6) for part number and supply voltage of AC Adaptor. 9.1.1.2. Handset Cross Reference:...
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.1.2. Check Battery Charge 9.1.2.1. Base Unit Cross Reference: Charge Circuit (P.12) 9.1.2.2. Handset Cross Reference: Check Power (P.34) Charge Circuit (P.12) 9.1.2.3. Charger Unit Cross Reference: Charge Circuit (P.12)
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.1.3. Check Link 9.1.3.1. Base Unit Note: (*1) Refer to Troubleshooting by Symptom (Base Unit and Charger Unit) (P.45) Cross Reference: Check Point (Base Unit) (P.45) Power Supply Circuit (P.9)
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Cross Reference: Check Point (Base Unit) (P.45)
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.1.3.2. Handset Note: (*1) Refer to Troubleshooting by Symptom (Handset) (P.49) Cross Reference: Check Point (Handset) (P.49) Power Supply Circuit/Reset Circuit (P.12)
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Cross Reference: Check Point (Handset) (P.49)
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.1.4. Check the RF part 9.1.4.1. Finding out the Defective part After All the Checkings or Repairing 1. Re-register the checked Handset to the checked Base Unit, and Regular HS to Regular BU. Note: If you need to register a handset, refer to Registering a Handset to a Base Unit (P.20)
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.1.4.2. RF Check Flowchart Each item (1 ~ 3) of RF Check Flowchart corresponds to Check Table for RF part (P.42). Please refer to the each item. Note: (*1) Base unit - refer to (G) of Check Point (Base Unit) (P.45)
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.1.4.3. Check Table for RF part Item BU (Base Unit) Check HS (Handset) Check Link Confirmation Normal 1. Register Regular HS to BU (to be 1. Register HS (to be checked) to Regular checked). HS, BU Mode: [Normal mode] 2.
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.1.5. Check Handset Transmission Cross Reference: Signal Route (P.14) 9.1.6. Check Handset Reception Cross Reference: How to Check the Handset Speaker or Receiver (P.68). Signal Route (P.14) 9.1.7. Check Caller ID Cross Reference: Signal Route (P.14)
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.1.8. Bell Reception 9.1.8.1. Base Unit 9.1.8.2. Handset Cross Reference: Telephone Line Interface (P.10) Check Link (P.36) How to Check the Handset Speaker or Receiver (P.68) 9.1.9. Check TAM Operation Cross Reference: Power Supply Circuit (P.9) Note: (*1) When replacing FLASH MEMORY (IC421), TAM data need to be written to it. Refer to Base Unit of Things to Do after...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.2. Troubleshooting by Symptom (Base Unit and Charger Unit) If your unit has below symptoms, follow the instructions in remedy column. Remedies depend on whether you have DECT tester (*1) or not. Note: (*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.
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Items Check Procedure Check or Point Replace Parts (G)* BBIC Clock Adjustment 1. Input Command “ sendchar WWD ff 48 IC 8006” X1, IC7, R430, VDD4 2. Confirm that the voltage between testpoint VDD4 and GND is less than 1.0 V.
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Items Check Procedure Check or Point Replace Parts (M)* Frequency Drift Confir- Follow steps 1 to 6 of (J). IC7, L7, C117, mation ANTI_TP 7.Confirm that the frequency drift is < ± 20 kHz/ms. C118, C124, C125, R106, R109,DA1,...
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Items Check Procedure Check or Point Replace Parts Audio Check 1. Link with Handset. IC7, SA1, L1, 2. Input -45 dBm/1kHz to MIC of Handset. L2, D3, Q3, Q4, Measure the Level at Line I/F and distortion level. R14, R15, R16, 3.
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 9.3. Troubleshooting by Symptom (Handset) If your unit has below symptoms, follow the instructions in remedy column. Remedies depend on whether you have DECT tester (*1) or not. Note: (*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.
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Items Check Procedure Check or Point Replace Parts (F)* Battery Monitor Check 1. Apply 2.25 V between BATT+ and BATT-. IC1, F1, C1, 2. Execute the command sendchar PAD sendchar LED 0 sendchar AD1 It assumes that the return value is XX.
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Items Check Procedure Check or Point Replace Parts (K)* Frequency Offset Confir- Follow steps 1 to 3 of (I). IC1, mation 4.Confirm that the frequency Offset is < ± 20 kHz. R801~R806, C808~C814, C819, C825, C834, IC801, L802~L804, D801, R807,...
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Items Check Procedure Check or Point Replace Parts (O) Audio Check and Confir- 1. Link to BASE which is connected to Line Simulator. IC1, R23, C12, mation 2. Set line voltage to 48 V and line current to 40 mA.
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11 Measurements and Adjustments 11.1. The Setting Method of JIG (Base Unit) 11.1.1. Preparation 11.1.1.1. Equipment Required • DECT tester: Rohde & Schwarz, CMD 60 is recommended. • Frequency counter: It must be precise enough to measure intervals of 1 Hz (precision; ±4 ppm).
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11.1.2.2. Batch file Setting Note: • “****” varies depending on the country. 11.1.2.3. Commands See the table below for frequently used commands. Command name Function Example rdeeprom Read the data of EEPROM Type “rdeeprom 00 00 FF”, and the data from address “00 00”...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11.2. Adjustment Standard (Base Unit) When connecting the simulator equipments for checking, please refer to below. 11.2.1. Bottom View Note: (A) - (S) is referred to Check Point (Base Unit) (P.45)
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11.3. Adjustment Standard (Charger Unit) When connecting the simulator equipment for checking, please refer to below. 11.3.1. Bottom View Digital Volt Meter /2 W DC POWER DC 6.5 V Note: (A) is referred to Check Point (Charger Unit) (P.48)
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11.4. The Setting Method of JIG (Handset) 11.4.1. Preparation 11.4.1.1. Equipment Required • DECT tester: Rohde & Schwarz, CMD 60 is recommended. • Frequency counter: It must be precise enough to measure intervals of 1 Hz (precision; ±4 ppm).
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11.4.2.2. Batch file Setting Note: • “*****” varies depending on the country. 11.4.2.3. Commands See the table below for frequently used commands. Command name Function Example rdeeprom Read the data of EEPROM Type “rdeeprom 00 00 FF”, and the data from address “00 00”...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11.5. Adjustment Standard (Handset) When connecting the simulator equipments for checking, please refer to below. 11.5.1. Component View Note: (A) - (Q) is referred to Check Point (Handset) (P.49)
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11.6. Things to Do after Replacing IC or X'tal Cautions: Some of the content on this page may not apply to models from some countries. 11.6.1. Base Unit Before making the following adjustment, ensure you have carried out PC Setting (P.58) in The Setting Method of JIG (Base Unit).
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11.6.2. Handset Before making the following adjustment, ensure you have carried out PC Setting (P.62) in The Setting Method of JIG (Hand- set). Items Necessary Adjustment BBIC (FLASH type) Programs for Voice processing, interface for RF 1. Make sure to connect the JIG cable, then detach the DC...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11.7. RF Specification 11.7.1. Base Unit Item Value Refer to -. * TX Power 19 dBm ~ 25 dBm Check Point (Base Unit) (J) Modulation -370±30/+370±30 kHz/div & Modulated Check Point (Base Unit) (K) width 690 kHz Frequency Offset...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 11.8. How to Check the Handset Speaker or Receiver 1. Prepare the digital voltmeter, and set the selector knob to ohm meter. 2. Put the probes at the speaker terminals as shown below. 11.9. Frequency Table (MHz) BASE UNIT...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 12.3. How to Replace the Flat Package IC Even if you do not have the special tools (for example, a spot heater) to remove the Flat IC, with some solder (large amount), a soldering iron and a cutter knife, you can easily remove the ICs that have more than 100 pins.
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 12.3.3. How to Install the IC 1. Temporarily fix the FLAT PACKAGE IC, soldering the two marked pins. *Check the accuracy of the IC setting with the corresponding soldering foil. 2. Apply flux to all pins of the FLAT PACKAGE IC.
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 12.4. Terminal Guide of the ICs, Transistors and Diodes 12.4.1. Base Unit 12.4.2. Handset 12.4.3. Charger Unit...
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 13 Schematic Diagram 13.1. For Schematic Diagram 13.1.1. Base Unit (Schematic Diagram (Base Unit_Main)) Notes: 1. DC voltage measurements are taken with voltmeter from the negative voltage line. 2. The schematic diagrams may be modified at any time with the development of new technology.
(*1) This cable is fixed by welding. Refer to How to Replace the Handset LCD (P.57). (*2) The rechargeable Ni-MH battery HHR-4MPT is available through sales route of Panasonic. (*3) Attach the spacer (No. 121) to the exact location described above.
KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT 15.5. Replacement Part List Safety Ref. Part No. Part Name & Description Remarks 1. RTL (Retention Time Limited) PQJJ1T039Y JACK, MODULAR Note: PNBC1002Y3 BUTTON, NAVIGATOR ABS-HB The “RTL” marking indicates that its Retention Time is PNHR1001Z GUIDE, BUTTON PS-HB...
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Safety Ref. Part No. Part Name & Description Remarks Safety Ref. Part No. Part Name & Description Remarks ERJ3GEYJ184 180k R804 ERJ2GEJ102 ERJ3GEYJ105 R805 ERJ2GEJ470 ERJ3GEYJ184 180k R806 ERJ2GEJ221 ERJ3GEYJ105 R807 ERJ2GEJ221 ERJ3GEYJ565 5.6M (CAPACITORS) ERJ3GEYJ104 100k F1K2H152A008 1.5n ERJ3GEYJ565 5.6M...
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Safety Ref. Part No. Part Name & Description Remarks Safety Ref. Part No. Part Name & Description Remarks C810 F1G1H1R6A480 1.6p PNKK1001Z6 LID, BATTERY (KX- ABS-HB TGA800BXS) C811 ECUE1H100DCQ 10p PNKK1001Z2 LID, BATTERY (KX- ABS-HB C812 F1G1H7R0A480 7p TGA800BXT) C813 F1G1H1R6A480 1.6p...
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KX-TG8021BXS/KX-TG8021BXT/KX-TGA800BXS/KX-TGA800BXT Safety Ref. Part No. Part Name & Description Remarks Safety Ref. Part No. Part Name & Description Remarks (CONNECTOR) ECUV1A105KBV 1 K1MY20BA0112 CONNECTOR PQCUV0J106KB 10 (RESISTORS) PQCUV0J106KB 10 ERJ2GEJ392 3.9k ECUE1H100DCQ 10p ERJ2GEJ102 ECUE1H100DCQ 10p ERJ2GEJ122 1.2k ECUE1H101JCQ 100p...
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ERG2SJ100E (FUSE) K5H302Y00003 FUSE 15.5.4. Accessories and Packing Materials Note: (*1) You can download and refer to the Operating Instruc- tions (Instruction book) on TSN Server. 15.5.4.1. KX-TG8021BXS/BXT Safety Ref. Part No. Part Name & Description Remarks PQLV207BXU AC ADAPTOR...