KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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...
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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) →D1→ IC1 → IC7 DC Jack (+6.5 V) →D1→...
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 6 Installation Instructions 6.2. Battery 6.2.1. Battery Installation 6.1. Connections See For Service Hint (P.27) 6.2.2. Battery Charge...
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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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 7 Operating Instructions 7.1. Programmable Settings You can customise the unit by programming the following features using the handset. 7.1.1. Programming by scrolling through the display menus...
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT *1 The item will not be reset when pressing keys. Refer to How to Clear User Setting (P.34). *2 The item will not be reset when pressing keys. Refer to How to Clear User Setting (P.34). Cross Reference: Registering a Handset to a Base Unit (P.21) 7.1.2.
• When you purchase an additional handset, refer to the additional handset's installation manual for registration. Cross Reference: For Service Hint (P.27) 7.2.1. Deregistering a Handset 7.3. Copying Phonebook Entries You can copy phonebook entries to the phonebook of another compatible Panasonic handset. Copying all entries 7.3.1.
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 8 Service Mode 8.1. Engineering Mode 8.1.1. Base Unit...
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT Frequently Used Items (Base Unit) ex.) Items Address Default Data New Data Remarks C-ID (FSK) sensitivity 04 B6 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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 Adjusted value Given value...
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421 Refer to the following procedures.
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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.21) •...
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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:...
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 9.1.3. Check Link 9.1.3.1. Base Unit Note: (*1) Refer to Troubleshooting by Symptom (Base Unit and Charger Unit) (P.47) Cross Reference: Check Point (Base Unit) (P.47) Power Supply Circuit (P.9)
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT Cross Reference: Check Point (Base Unit) (P.47)
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 9.1.3.2. Handset Note: (*1) Refer to Troubleshooting by Symptom (Handset) (P.51) Cross Reference: Check Point (Handset) (P.51) Power Supply Circuit/Reset Circuit (P.12)
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT Cross Reference: Check Point (Handset) (P.51)
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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.21)
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 9.1.4.2. RF Check Flowchart Each item (1 ~ 3) of RF Check Flowchart corresponds to Check Table for RF part (P.44). Please refer to the each item. Note: (*1) Base unit - refer to (G) of Check Point (Base Unit) (P.47)
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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.
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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.70). Signal Route (P.14) 9.1.7. Check Caller ID Cross Reference: Signal Route (P.14)
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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.38) How to Check the Handset Speaker or Receiver (P.70) 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT Items Check Procedure Check or Point Replace Parts 1. Connect Telephone Socket to Tel-simulator which is connected with 600 Ω. (H)* Hookswitch Check with L1, L2, Q3, R14, DC Characteristics 2. Set line voltage to 48 V and line current to 40mA at off-hook condition of nor- R15, Q4, R16, mal telephone.
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT Items Check Procedure Check or Point Replace Parts (M)* Frequency Drift Confir- Follow steps 1 to 6 of (J). IC7, mation ANTI_TP 7.Confirm that the frequency drift is < ± 35 kHz/ms. C802~C806, C808~C814, C820, C819, C822, C823, C825, C827,...
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT Items Check Procedure Check or Point Replace Parts Audio Check 1. Link with Handset. IC7, SA1, L1, 2. Input -45dBm/1kHz to MIC of Handset. L2, D3, Q3, Q4, Measure the Level at Line I/F and distortion level. R14, R15, R16, 3.
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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 R12, R45 sendchar PAD sendchar LED 0 sendchar CRX 0 1 sendchar AD1 It assumes that the return value is XX.
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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 < ± 50 kHz. C802~C806, C808~C814, C819~C820, C822, C825~C827, C834, C859~C864, L801~L804,...
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 9.3.2. Troubleshooting for Speakerphone When the customer’s telephone line corresponds to the following conditions, and the transmission signal of SP-Phone is inter- rupted, performing the next set up to a cordless handset will improve it to some extent. Conditions 1.
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11 Measurements and Adjustments This chapter explains the measuring equipment, the JIG connection, and the PC setting method necessary for the measurement in Troubleshooting Guide (P.35) 11.1. Equipment Required • Digital multi-meter (DMM): it must be able to measure voltage and current.
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11.2.2. How to install Batch file into P.C. Note: • “*****” varies depending on the country or models. 11.2.3. 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11.3. Adjustment Standard (Base Unit) When connecting the simulator equipment for checking, please refer to below. 11.3.1. Bottom View Note: (A) - (T) is referred to Check Point (Base Unit) (P.47)
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11.4. Adjustment Standard (Charger Unit) When connecting the simulator equipment for checking, please refer to below. 11.4.1. Bottom View Digital Volt Meter /2 W DC POWER DC 6.5 V Note: (A) is referred to Check Point (Charger Unit) (P.50)
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11.5. The Setting Method of JIG (Handset) This section explains the PC setting to use command required in Check Point (Handset)(P.51). <Preparation> Note: *: If you have the JIG Cable for TCD500 series • Serial JIG cable: PQZZ1CD300E* (PQZZ1CD505E), change the following values of resis- •...
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11.5.2. How to install Batch file into P.C. Note: • “*****” varies depending on the country or models. 11.5.3. 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11.6. Adjustment Standard (Handset) When connecting the simulator equipments for checking, please refer to below. 11.6.1. Component View PNLB1103Z TP_ANT1 KX-TGA641 EUDECT KX-TGA106 USDECT RECEIVER RED (EU) BLACK (EU) BLUE (US) WHITE (EU) C70 C152 C71 C138 C139 BLACK...
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11.7. Things to Do after Replacing IC or X'tal If repairing or replacing BBIC (FLASH type), EEPROM and X'tal, it is necessary to download the required data such as Program- ming data or adjustment data, etc in memory. The set doesn't operate if it is not executed.
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11.7.1.2. Handset First, operate the PC setting according to The Setting Method of JIG (Handset)(P.64). Then download the appropriate data according to the following procedures. Items How to download/Required adjustment BBIC (FLASH type) Programming data is stored in memory.
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11.8. RF Specification 11.8.1. 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 11.9. 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. 11.10. Frequency Table (MHz) BASE UNIT...
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 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-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 12.4. How to Replace the LLP (Leadless Leadframe Package) IC 12.4.1. Preparation • PbF (: Pb free) Solder • Soldering Iron Tip Temperature of 700°F ± 20°F (370°C ± 10°C) Note: We recommend a 30 to 40 Watt soldering iron. An expert may be able to use a 60 to 80 Watt iron where someone with less experience could overheat and damage the PCB foil.
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 12.4.4. How to Install the Shield Case Note: • If you don’t have special tools (ex. Hot air disordering tool), conduct the following operations. • Shield case’s No. : PNMC1013Z 1. Put the shield case. 2. Solder the surroundings.
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 12.5. Terminal Guide of the ICs, Transistors and Diodes 12.5.1. Base Unit 12.5.2. Handset 12.5.3. Charger Unit...
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 13 Schematic Diagram 13.1. For Schematic Diagram 13.1.1. Base Unit (Schematic Diagram (Base Unit)) 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.
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 13.2. Schematic Diagram (Base Unit) ANT1_TP ANT2_TP ANT_1 ANT_2 C851 C853 W 0.15mm W 0.15mm L 22+/-4mm L 22+/-4mm Beep 1st or 4th layer 1st or 4th layer Bell signal DA802 *R86 W 0.15mm L 22+/-4mm 1st or 4th layer W 0.15mm...
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT Loop Current LINE_DC *R30 100k (1005) NC C155 5.6k *R13 TP10 *R20 4.7k R116 3.9k 100k +1.8V 5.6M +1.8V 100k GND GND HAK_CL1 5.6M Caller ID RX_AF Bell signal 180k 4.7M 680p *C147 TX _AF 180k 4.7M *C148 Bell signal 680p 1.8V...
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT W 0.15mm L 20+/-2mm 3rd layer R807 RXON L801 C827 TP_ANT1 RX_RF C826 C803 RF_RXn *C859 1.5p DA801 RF_RXp W 0.125mm L 7.6mm CP+3.0V Gap 0.125mm W 0.15mm W 0.15mm 1st layer L 5.0mm L 5.0mm 1st layer 1st layer C172 K0.1u...
KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT 15 Exploded View and Replacement Parts List 15.1. Cabinet and Electrical Parts (Base Unit) Note: (*1) Refer to the spacer (No. 109) of Cabinet and Electrical Parts (Handset) (P.97).
(*1) This cable is fixed by welding. Refer to How to Replace the Handset LCD (P.59). (*2) The rechargeable Ni-MH battery P03P, HHR-4MRE or HHR-4MPT is available through sales route of Panasonic. (*3) Attach the spacer (No. 122) to the exact location described above.
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT Safety Ref. Part No. Part Name & Description Remarks Safety Ref. Part No. Part Name & Description Remarks PQ4R10XJ184 180k (CAPACITORS) PQ4R10XJ105 F1K2H681A008 680p PQ4R10XJ184 180k F1K2H681A008 680p PQ4R10XJ105 ECUV1C103KBV 0.01 ERJ3GEYJ565 5.6M ECUV1C103KBV 0.01 ERJ3GEYJ104 100k ECUV1C104KBV 0.1 ERJ3GEYJ565 5.6M...
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT Safety Ref. Part No. Part Name & Description Remarks Safety Ref. Part No. Part Name & Description Remarks C802 F1G1H1R8A480 1.8p L0AA02A00095 SPEAKER C803 F1G1H1R5A480 1.5p PQHS10784Y SPACER, SPEAKER NET C804 F1G1H1R8A480 1.8p PQJC10056X BATTERY TERMINAL C805 F1G1H3R3A480 3.3p...
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KX-TG6421FXS/KX-TG6421FXT/KX-TGA641FXS/KX-TGA641FXT Safety Ref. Part No. Part Name & Description Remarks Safety Ref. Part No. Part Name & Description Remarks (COMPONENTS PARTS) ECUE1A104KBQ 0.1 D1H810240004 RESISTOR ARRAY ECUE1H100DCQ 10p D1H410220001 RESISTOR ARRAY ECUE1A104KBQ 0.1 D1H433220001 RESISTOR ARRAY ECUE1A104KBQ 0.1 RA61 D1H422120001 RESISTOR ARRAY...
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IRON (*2) (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-TG6421FXS/FXT Safety Ref. Part No. Part Name & Description Remarks PQLV219CEY AC ADAPTOR...